What is WiMAX

Information Provided By Intel And howstuffworks

WiMAX is an IP based, wireless broadband access technology that provides performance similar to 802.11/Wi-Fi networks with the coverage and QOS (quality of service) of cellular networks. WiMAX is also an acronym meaning "Worldwide Interoperability for Microwave Access (WiMAX).

WiMAX is a wireless digital communications system, also known as IEEE 802.16, that is intended for wireless "metropolitan area networks". WiMAX can provide broadband wireless access (BWA) up to 30 miles (50 km) for fixed stations, and 3 - 10 miles (5 - 15 km) for mobile stations. In contrast, the WiFi/802.11 wireless local area network standard is limited in most cases to only 100 - 300 feet (30 - 100m).

With WiMAX, WiFi-like data rates are easily supported, but the issue of interference is lessened. WiMAX operates on both licensed and non-licensed frequencies, providing a regulated environment and viable economic model for wireless carriers.

At its heart, however, WiMAX is a standards initiative. Its purpose is to ensure that the broadband wireless radios manufactured for customer use interoperate from vendor to vendor. The primary advantages of the WiMAX standard are to enable the adoption of advanced radio features in a uniform fashion and reduce costs for all of the radios made by companies, who are part of the WiMAX Forum™ - a standards body formed to ensure interoperability via testing. The more recent Long Term Evolution (LTE) standard is a similar term describing a parallel technology to WiMAX that is being developed by vendors and carriers as a counterpoint to WiMAX.

Laptop Image Gallery

A model displays a laptop computer equipped with WiMAX technology. See more laptop pictures.

PATRICK LIN/AFP/Getty Images

Think about how you access the Internet today. There are basically three different options:

• Broadband access - In your home, you have either a DSL or cable modem. At the office, your company may be using a T1 or a T3 line.
• WiFi access - In your home, you may have set up a WiFi router that lets you surf the Web while you lounge with your laptop. On the road, you can find WiFi hot spots in restaurants, hotels, coffee shops and libraries.
• Dial-up access - If you are still using dial-up, chances are that either broadband access is not available, or you think that broadband access is too expensive.

The main problems with broadband access are that it is pretty expensive and it doesn't reach all areas. The main problem with WiFi access is that hot spots are very small, so coverage is sparse.

What if there were a new technology that solved all of these problems? This new technology would provide:

• The high speed of broadband service
• Wireless rather than wired access, so it would be a lot less expensive than cable or DSL and much easier to extend to suburban and rural areas
• Broad coverage like the cell phone network instead of small WiFi hotspots

This system is actually coming into being right now, and it is called WiMAX. WiMAX is short forWorldwide Interoperability for Microwave Access, and it also goes by the IEEE name 802.16. ­

WiMAX has the potential to do to broadband Internet access what cell phones have done to phone access. In the same way that many people have given up their "land lines" in favor of cell phones, WiMAX could replace cable and DSL services, providing universal Internet access just about anywhere you go. WiMAX will also be as painless as WiFi -- turning your computer on will automatically connect you to the closest available WiMAX antenna.

In this article, we'll find out how WiMAX works, what engineers are doing to make it better and what it could mean for the future of wireless Internet.

WiMAX transmitting tower

Photo courtesy Intel

WiMAX Wireless Network

In practical terms, WiMAX would operate similar to WiFi but at higher speeds, over greater distances and for a greater number of users. WiMAX could potentially erase the suburban and rural blackout areas that currently have no broadband Internet access because phone andcable companies have not yet run the necessary wires to those remote locations.

A WiMAX system consists of two parts:

• A WiMAX tower, similar in concept to a cell-phone tower - A single WiMAX tower can provide coverage to a very large area -- as big as 3,000 square miles (~8,000 square km).
• A WiMAX receiver - The receiver and antenna could be a small box or PCMCIA card, or they could be built into a laptop the way WiFi access is today.

A WiMAX tower station can connect directly to the Internet using a high-bandwidth, wired connection (for example, a T3 line). It can also connect to another WiMAX tower using a line-of-sight, microwave link. This connection to a second tower (often referred to as a backhaul), along with the ability of a single tower to cover up to 3,000 square miles, is what allows WiMAX to provide coverage to remote rural areas.

HowStuffWorks.com

What this points out is that WiMAX actually can provide two forms of wireless service:

• There is the non-line-of-sight, WiFi sort of service, where a small antenna on your computer connects to the tower. In this mode, WiMAX uses a lower frequency range -- 2 GHz to 11 GHz (similar to WiFi). Lower-wavelength transmissions are not as easily disrupted by physical obstructions -- they are better able to diffract, or bend, around obstacles.
• There is line-of-sight service, where a fixed dish antenna points straight at the WiMAX tower from a rooftop or pole. The line-of-sight connection is stronger and more stable, so it's able to send a lot of data with fewer errors. Line-of-sight transmissions use higher frequencies, with ranges reaching a possible 66 GHz. At higher frequencies, there is less interference and lots more bandwidth.

WiFi-style access will be limited to a 4-to-6 mile radius (perhaps 25 square mile­s or 65 square km of coverage, which is similar in range to a cell-phone zone). Through the stronger line-of-sight antennas, the WiMAX transmitting station would send data to WiMAX-enabled computers or routers set up within the transmitter's 30-mile radius (2,800 square miles or 9,300 square km of coverage). This is what allows WiMAX to achieve its maximum range.

The final step in the area network scale is the global area network (GAN). The proposal for GAN is IEEE 802.20. A true GAN would work a lot like today's cell phone networks, with users able to travel across the country and still have access to the network the whole time. This network would have enough bandwidth to offer Internet access comparable to cable modem service, but it would be accessible to mobile, always-connected devices like laptops or next-generation cell phones.

INTEL PAVES THE WAY

Intel will start making their Centrino laptop processors WiMAX enabled in the next two to three years. This will go a long way toward making WiMAX a success. If everyone's laptop already has it (which is predicted by 2008), it will be much less risky for companies to set up WiMAX base stations. Intel also announced that it would be partnering with a company called Clearwire to push WiMAX even further ahead. Clearwire plans to send data from WiMAX base stations to small wireless modems. See Intel, Clearwire to Accelerate Deployment of WiMAX Networks Worldwide (Oct. 25, 2004).

WiMAX Coverage and Speed

WiMAX operates on the same general principles as WiFi -- it sends data from one computer to another via radio signals. A computer (either a desktop or a laptop) equipped with WiMAX would receive data from the WiMAX transmitting station, probably usingencrypted data keys to prevent unauthorized users from stealing access.

The fastest WiFi connection can transmit up to 54 megabits per second under optimal conditions. WiMAX should be able to handle up to 70 megabits per second. Even once that 70 megabits is split up between several dozen businesses or a few hundred home users, it will provide at least the equivalent of cable-modem transfer rates to each user.

The biggest difference isn't speed; it's distance. WiMAX outdistances WiFi by miles. WiFi's range is about 100 feet (30 m). WiMAX will blanket a radius of 30 miles (50 km) with wireless access. The increased range is due to the frequencies used and the power of the transmitter. Of course, at that distance, terrain, weather and large buildings will act to reduce the maximum range in some circumstances, but the potential is there to cover huge tracts of land.

IEEE 802.16 Specifications

• Range - 30-mile (50-km) radius from base station
• Speed - 70 megabits per second
• Line-of-sight not needed between user and base station
• Frequency bands - 2 to 11 GHz and 10 to 66 GHz (licensed and unlicensed bands)
• Defines both the MAC and PHY layers and allows multiple PHY-layer specifications (See How OSI Works)
  
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  Logo courtesy Intel

  WiMAX Cost

  A citywide blanket coverage of wireless Internet access sounds great, but companies aren't going to go around setting up WiMAX base stations out of sheer kindness. Who's going to pay for WiMAX?

  It depends how it will be used. There are two ways WiMAX can be implemented -- as a zone for wireless connections that single users go to when they want to connect to the Internet on a laptop (the non-line-of-sight "super WiFi" implementation), or as a line-of-sight hub used to connect hundreds of customers to a steady, always-on, high-speed wireless Internet connection.

  Under the "super WiFi" plan, cities might pay to have WiMAX base stations set up in key areas for business and commerce and then allow people to use them for free. They already do this with WiFi, but instead of putting in a bunch of WiFi hot spots that cover a few hundred square yards, a city could pay for one WiMAX base station and cover an entire financial district. This could provide a strong draw when city leaders try to attract businesses to their area.

  Some companies might set up WiMAX transmitters and then make people pay for access. Again, this is similar to strategies used for WiFi, but a much wider area would be covered. Instead of hopping from one hot spot to another, WiMAX-enabled users could have Internet access anywhere within 30 miles of the WiMAX base station. These companies might offer unlimited access for a monthly fee or a "pay as you go" plan that charges on a per-minute or per-hour basis.

  The high-speed wireless hub plan has the potential to be far more revolutionary. If you have high-speed Internet access now, it probably works something like this: The cable (or phone) company has a line that runs into your home. That line goes to a cable modem, and another line runs from the modem to your computer. If you have a home network, first it goes to a router and then on to the other computers on the network. You pay the cable company a monthly fee, which reflects in part the expense of running cable lines to every single home in the neighborhood.

  On the next page, we'll discuss how WiMAX can work for you

  NETWORK SCALE

  The smallest-scale network is a personal area network (PAN). A PAN allows devices to communicate with each other over short distances. Bluetooth is the best example of a PAN.

  The next step up is a local area network (LAN). A LAN allows devices to share information, but is limited to a fairly small central area, such as a company's headquarters, a coffee shop or your house. Many LANs use WiFi to connect the network wirelessly.

  WiMAX is the wireless solution for the next step up in scale, the metropolitan area network (MAN). A MAN allows areas the size of cities to be connected.

  WiMAX Technology at Home

  Here's what would happen if you got WiMAX. An Internet service provider sets up a WiMAX base station 10 miles from your home. You would buy a WiMAX-enabled computer or upgrade your old computer to add WiMAX capability. You would receive a special encryption code that would give you access to the base station. The base station would beam data from the Internet to your computer (at speeds potentially higher than today's cable modems), for which you would pay the provider a monthly fee. The cost for this service could be much lower than current high-speed Internet-subscription fees because the provider never had to run cables.

  If you have a home network, things wouldn't change much. The WiMAX base station would send data to a WiMAX-enabled router, which would then send the data to the different computers on your network. You could even combine WiFi with WiMAX by having the router send the data to the computers via WiFi.

  WiMAX doesn't just pose a threat to providers of DSL and cable-modem service. The WiMAX protocol is designed to accommodate several different methods of data transmission, one of which is Voice Over Internet Protocol (VoIP). VoIP allows people to make local, long-distance and even international calls through a broadband Internet connection, bypassing phone companies entirely. If WiMAX-compatible computers become very common, the use of VoIP could increase dramatically. Almost anyone with a laptop could make VoIP calls.

  For more information on WiMAX, wireless networking and related topics, check out the links on the next page.

  
  

What Is a Protocol

What is a Protocol?

A protocol is a set of rules that governs the communications between computers on a network. In order for two computers to talk to each other, they must be speaking the same language. Many different types of network protocols and standards are required to ensure that your computer (no matter which operating system, network card, or application you are using) can communicate with another computer located on the next desk or half-way around the world. The OSI (Open Systems Interconnection) Reference Model defines seven layers of networking protocols. The complexity of these layers is beyond the scope of this tutorial; however, they can be simplified into four layers to help identify some of the protocols with which you should be familiar (see fig 1).

OSI Layer	Name	Common Protocols
7	Application	HTTP | FTP | SMTP | DNS | Telnet
6	Presentation
5	Session
4	Transport	TCP | SPX
3	Network	IP | IPX
2	Data Link	Ethernet
1	Physical

Fig 1. OSI model related to common network protocols

Figure 1 illustrates how some of the major protocols would correlate to the OSI model in order to communicate via the Internet. In this model, there are four layers, including:

• Ethernet (Physical/Data Link Layers)
• IP/IPX (Network Layer)
• TCP/SPX (Transport Layer)
• HTTP, FTP, Telnet, SMTP, and DNS(combined Session/Presentation/Application Layers)

Assuming you want to send an e-mail message to someone in Italy, we will examine the layers "from the bottom up" -- beginning with Ethernet (physical/data link layers).

Ethernet (Physical/Data Link Layers)

The physical layer of the network focuses on hardware elements, such as cables, repeaters, and network interface cards. By far the most common protocol used at the physical layer is Ethernet. For example, an Ethernet network (such as 10BaseT or 100BaseTX) specifies the type of cables that can be used, the optimal topology (star vs. bus, etc.), the maximum length of cables, etc. (See the Cabling section for more information on Ethernet standards related to the physical layer).

The data link layer of the network addresses the way that data packets are sent from one node to another. Ethernet uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection). This is a system where each computer listens to the cable before sending anything through the network. If the network is clear, the computer will transmit. If some other node is already transmitting on the cable, the computer will wait and try again when the line is clear. Sometimes, two computers attempt to transmit at the same instant. When this happens a collision occurs. Each computer then backs off and waits a random amount of time before attempting to retransmit. With this access method, it is normal to have collisions. However, the delay caused by collisions and retransmitting is very small and does not normally effect the speed of transmission on the network.

Ethernet

The original Ethernet standard was developed in 1983 and had a maximum speed of 10 Mbps (phenomenal at the time) over coaxial cable. The Ethernet protocol allows for bus, star, or tree topologies, depending on the type of cables used and other factors. This heavy coaxial cabling was expensive to purchase, install, and maintain, and very difficult to retrofit into existing facilities.

The current standards are now built around the use of twisted pair wire. Common twisted pair standards are 10BaseT, 100BaseT, and 1000BaseT. The number (10, 100, 1000) ands for the speed of transmission (10/100/1000 megabits per second); the "Base" stands for "baseband" meaning it has full control of the wire on a single frequency; and the "T" stands for "twisted pair" cable. Fiber cable can also be used at this level in 10BaseFL.

Fast Ethernet

The Fast Ethernet protocol supports transmission up to 100 Mbps. Fast Ethernet requires the use of different, more expensive network concentrators/hubs and network interface cards. In addition, category 5 twisted pair or fiber optic cable is necessary. Fast Ethernet standards include:

• 100BaseT - 100 Mbps over 2-pair category 5 or better UTP cable.
• 100BaseFX - 100 Mbps over fiber cable.
• 100BaseSX -100 Mbps over multimode fiber cable.
• 100BaseBX - 100 Mbps over single mode fiber cable.

Gigabit Ethernet

Gigabit Ethernet standard is a protocol that has a transmission speed of 1 Gbps (1000 Mbps). It can be used with both fiber optic cabling and copper. (see the Cabling section for more information).

• 1000BaseT - 1000 Mbps over 2-pair category 5 or better UTP cable.
• 1000BaseTX - 1000 Mbps over 2-pair category 6 or better UTP cable.
• 1000BaseFX - 1000 Mbps over fiber cable.
• 1000BaseSX -1000 Mbps over multimode fiber cable.
• 1000BaseBX - 1000 Mbps over single mode fiber cable.

The Ethernet standards continue to evolve. with 10 Gigabit Ethernet (10,000 Mbps) and 100 Gigabit Ethernet (100,000 Mbps),

Ethernet Protocol Summary

Protocol	Cable	Speed
Ethernet	Twisted Pair, Coaxial, Fiber	10 Mbps
Fast Ethernet	Twisted Pair, Fiber	100 Mbps
Gigabit Ethernet	Twisted Pair, Fiber	1000 Mbps

Older Network Protocols

Several very popular network protocols, commonly used in the 90's and early 21st century have now largely fallen into disuse. While you may hear terms from time to time, such as "Localtalk" (Apple) or "Token Ring" (IBM), you will rarely find these systems still in operation. Although they played an important role in the evolution of networking, their performance and capacity limitations have relegated them to the past, in the wake of the standardization of Ethernet driven by the success of the Internet.

IP and IPX (Network Layer)

The network layer is in charge of routing network messages (data) from one computer to another. The common protocols at this layer are IP (which is paired with TCP at the transport layer for Internet network) and IPX (which is paired with SPX at the transport layer for some older Macintosh, Linus, UNIX, Novell and Windows networks). Because of the growth in Internet-based networks, IP/TCP are becoming the leading protocols for most networks.

Every network device (such as network interface cards and printers) have a physical address called a MAC (Media Access Control) address. When you purchase a network card, the MAC address is fixed and cannot be changed. Networks using the IP and IPX protocols assign logical addresses (which are made up of the MAC address and the network address) to the devices on the network, This can all become quite complex -- suffice it to say that the network layer takes care of assigning the correct addresses (via IP or IPX) and then uses routers to send the data packets to other networks.

TCP and SPX (Transport Layer)

The transport layer is concerned with efficient and reliable transportation of the data packets from one network to another. In most cases, a document, e-mail message or other piece of information is not sent as one unit. Instead, it is broken into small data packets, each with header information that identifies its correct sequence and document.

When the data packets are sent over a network, they may or may not take the same route -- it doesn't matter. At the receiving end, the data packets are re-assembled into the proper order. After all packets are received, a message goes back to the originating network. If a packet does not arrive, a message to "re-send" is sent back to the originating network.

TCP, paired with IP, is by far the most popular protocol at the transport level. If the IPX protocol is used at the network layer (on networks such as Novell or Microsoft), then it is paired with SPX at the transport layer.

HTTP, FTP, SMTP and DNS (Session/Presentation/Application Layers)

Several protocols overlap the session, presentation, and application layers of networks. There protocols listed below are a few of the more well-known:

• DNS - Domain Name System - translates network address (such as IP addresses) into terms understood by humans (such as Domain Names) and vice-versa
• DHCP - Dynamic Host Configuration Protocol - can automatically assign Internet addresses to computers and users
• FTP - File Transfer Protocol - a protocol that is used to transfer and manipulate files on the Internet
• HTTP - HyperText Transfer Protocol - An Internet-based protocol for sending and receiving webpages
• IMAP - Internet Message Access Protocol - A protocol for e-mail messages on the Internet
• IRC - Internet Relay Chat - a protocol used for Internet chat and other communications
• POP3 - Post Office protocol Version 3 - a protocol used by e-mail clients to retrieve messages from remote servers
• SMTP - Simple Mail Transfer Protocol - A protocol for e-mail messages on the Internet

What is a Network?

What is a Network?

A network consists of two or more computers that are linked in order to share resources (such as printers and CDs), exchange files, or allow electronic communications. The computers on a network may be linked through cables, telephone lines, radio waves, satellites, or infrared light beams.

Two very common types of networks include:

• Local Area Network (LAN)
• Wide Area Network (WAN)

You may also see references to a Metropolitan Area Networks (MAN), a Wireless LAN (WLAN), or a Wireless WAN (WWAN).

Local Area Network

A Local Area Network (LAN) is a network that is confined to a relatively small area. It is generally limited to a geographic area such as a writing lab, school, or building.

Computers connected to a network are broadly categorized as servers or workstations. Servers are generally not used by humans directly, but rather run continuously to provide "services" to the other computers (and their human users) on the network. Services provided can include printing and faxing, software hosting, file storage and sharing, messaging, data storage and retrieval, complete access control (security) for the network's resources, and many others.

Workstations are called such because they typically do have a human user which interacts with the network through them. Workstations were traditionally considered a desktop, consisting of a computer, keyboard, display, and mouse, or a laptop, with with integrated keyboard, display, and touchpad. With the advent of the tablet computer, and the touch screen devices such as iPad and iPhone, our definition of workstation is quickly evolving to include those devices, because of their ability to interact with the network and utilize network services.

Servers tend to be more powerful than workstations, although configurations are guided by needs. For example, a group of servers might be located in a secure area, away from humans, and only accessed through the network. In such cases, it would be common for the servers to operate without a dedicated display or keyboard. However, the size and speed of the server's processor(s), hard drive, and main memory might add dramatically to the cost of the system. On the other hand, a workstation might not need as much storage or working memory, but might require an expensive display to accommodate the needs of its user. Every computer on a network should be appropriately configured for its use.

On a single LAN, computers and servers may be connected by cables or wirelessly. Wireless access to a wired network is made possible by wireless access points (WAPs). These WAP devices provide a bridge between computers and networks. A typical WAP might have the theoretical capacity to connect hundreds or even thousands of wireless users to a network, although practical capacity might be far less.

Nearly always servers will be connected by cables to the network, because the cable connections remain the fastest. Workstations which are stationary (desktops) are also usually connected by a cable to the network, although the cost of wireless adapters has dropped to the point that, when installing workstations in an existing facility with inadequate wiring, it can be easier and less expensive to use wireless for a desktop.

See the Topology, Cabling, and Hardware sections of this tutorial for more information on the configuration of a LAN.

Wide Area Network

Wide Area Networks (WANs) connect networks in larger geographic areas, such as Florida, the United States, or the world. Dedicated transoceanic cabling or satellite uplinks may be used to connect this type of global network.

Using a WAN, schools in Florida can communicate with places like Tokyo in a matter of seconds, without paying enormous phone bills. Two users a half-world apart with workstations equipped with microphones and a webcams might teleconference in real time. A WAN is complicated. It uses multiplexers, bridges, and routers to connect local and metropolitan networks to global communications networks like the Internet. To users, however, a WAN will not appear to be much different than a LAN.

Advantages of Installing a School Network

User access control.

Modern networks almost always have one or more servers which allows centralized management for users and for network resources to which they have access. User credentials on a privately-owned and operated network may be as simple as a user name and password, but with ever-increasing attention to computing security issues, these servers are critical to ensuring that sensitive information is only available to authorized users.

Information storing and sharing.

Computers allow users to create and manipulate information. Information takes on a life of its own on a network. The network provides both a place to store the information and mechanisms to share that information with other network users.

Connections.

Administrators, instructors, and even students and guests can be connected using the campus network.

Services.

The school can provide services, such as registration, school directories, course schedules, access to research, and email accounts, and many others. (Remember, network services are generally provided by servers).

Internet.

The school can provide network users with access to the internet, via an internet gateway.

Computing resources.

The school can provide access to special purpose computing devices which individual users would not normally own. For example, a school network might have high-speed high quality printers strategically located around a campus for instructor or student use.

Flexible Access.

School networks allow students to access their information from connected devices throughout the school. Students can begin an assignment in their classroom, save part of it on a public access area of the network, then go to the media center after school to finish their work. Students can also work cooperatively through the network.

Workgroup Computing.

Collaborative software allows many users to work on a document or project concurrently. For example, educators located at various schools within a county could simultaneously contribute their ideas about new curriculum standards to the same document, spreadsheets, or website.

Disadvantages of Installing a School Network

Expensive to Install.

Large campus networks can carry hefty price tags. Cabling, network cards, routers, bridges, firewalls, wireless access points, and software can get expensive, and the installation would certainly require the services of technicians. But, with the ease of setup of home networks, a simple network with internet access can be setup for a small campus in an afternoon.

Requires Administrative Time.

Proper maintenance of a network requires considerable time and expertise. Many schools have installed a network, only to find that they did not budget for the necessary administrative support.

Servers Fail.

Although a network server is no more susceptible to failure than any other computer, when the files server "goes down" the entire network may come to a halt. Good network design practices say that critical network services (provided by servers) should be redundant on the network whenever possible.

Cables May Break.

The Topology chapter presents information about the various configurations of cables. Some of the configurations are designed to minimize the inconvenience of a broken cable; with other configurations, one broken cable can stop the entire network.

Security and compliance.

Network security is expensive. It is also very important. A school network would possibly be subject to more stringent security requirements than a similarly-sized corporate network, because of its likelihood of storing personal and confidential information of network users, the danger of which can be compounded if any network users are minors. A great deal of attention must be paid to network services to ensure all network content is appropriate for the network community it serves.

Photoshop Brushes - Create Your Own Custom Brushes

Step 1: Create A New Photoshop Document

Let's begin by creating a brand new Photoshop document which we'll use to design our brush. Again, the purpose of this tutorial is not to learn how to create this exact brush, but rather to see how the process works from beginning to end. I'm going to create a new 200 x 200 pixel document by going up to the File menu in the Menu Bar at the top of the screen and choosing New. Or, for a faster way to create a new document, press Ctrl+N (Win) / Command+N (Mac) on your keyboard:

Go to File > New.

This opens the New Document dialog box. Enter 200 for both the Width and Height options and make sure the measurement type is set to pixels. Also, make sure the Background Contents option is set to White since we need white to be the background color for the brush:

Create a new 200 x 200 pixel document with a white background.

Click OK when you're done to accept the settings and exit out of the dialog box. A new 200 x 200 pixel document, filled with white, will appear on your screen.

Choosing An Initial Size For Your Brush
Photoshop allows us to create brushes as large as 2500 x 2500 pixels, but as they say, just because you can doesn't mean you should. At that size, you'd be painting with the virtual equivalent of a floor mop. Also, painting with very large brushes requires a lot more memory and horse power from your computer which can slow your system down considerably. For typical work, you'll want to create brushes much smaller.

The size at which you initially create the brush will become its default size, and it's important to note that brushes we create ourselves are pixel-based brushes, which means they're essentially images and behave exactly the same way as regular images when it comes to resizing them. Brushes will usually remain crisp and sharp when we make them smaller, but if you increase their size much beyond the default, they'll become soft and dull looking. The general idea, then, is to create your new brush just large enough to suit your needs, which may involve a little trial and error. The 200 x 200 pixel size I'm using here usually works well.

Step 2: Select The Brush Tool

Let's create our new brush using one of Photoshop's built-in brushes. First, select the Brush Tool from the Tools palette, or press the letter B on your keyboard to quickly select it with the shortcut:

Select the Brush Tool.

Step 3: Select A Small Round Brush

With the Brush Tool selected, right-click (Win) / Control-click (Mac) anywhere inside the document window to display the Brush Preset picker, which is a miniature version of the full-blown Brushes panel that we'll look at a bit later (and we'll examine in much more detail in another tutorial). The Brush Preset picker allows us to choose from a list of preset brushes (which explains its name). To select a brush, simply click on its thumbnail. I'm going to click on the Hard Round 5 Pixels brush to select it. If you have Tool Tips enabled in Photoshop's Preferences, the name of each brush will appear as you hover over the thumbnails. Press Enter (Win) /Return (Mac) once you've chosen your brush to close out of the palette:

Select a small round brush from the Preset picker, then press Enter (Win) / Return (Mac) to close out of it.

Step 4: Make Sure The Foreground Color Is Set To Black

Back when we created our new document in Step 1, we made sure to set the background color of our document to white. The reason is that all brushes in Photoshop are Grayscale, meaning that a brush can contain only black, white, or shades of gray in between. Areas filled with white become transparent, so you won't see them when you're painting with the brush. Areas filled with black will be 100% visible, and if your brush includes various shades of gray, those areas will be partially visible depending on how close they are to black or white, with darker shades of gray being more visible than lighter shades.

If we were to turn our new document into a brush as it is right now, the entire brush would be transparent since it contains nothing but white. Painting with an invisible brush may make an interesting statement artistically, but for more practical purposes (like this tutorial), you'll most likely want a brush you can actually see, which means we'll need to add some areas of black to the document. The black areas will become the visible shape of the brush (known as the brush tip).

Photoshop paints using the current Foreground color, and as luck would have it, the default for the Foreground color is black, which means there's a very good chance yours is already set to black. You can see the current Foreground and Background colors by looking at their color swatches near the bottom of the Tools palette (the Foreground color is the swatch in the top left). If your Foreground color is set to something other than black, press the letter D on your keyboard to quickly reset both the Foreground and Background colors to their defaults:

The Foreground color is the color the brush will paint with.

Step 5: Paint A Series Of Horizontal Brush Strokes Inside The Document Window

With the small round brush selected and black as your Foreground color, click inside the document window and paint a series of short horizontal brush strokes. For added variety, alter the thickness of the strokes by changing the size of the brush using the handy keyboard shortcuts. Press the left bracket key ( [ ) to make the brush smaller or the right bracket key ( ] ) to make it larger. You'll find the bracket keys to the right of the letter P on most keyboards. When you're done, you should have a column of brush strokes that looks something like this:

A column of messy, random brush strokes.

Step 6: Create A New Brush From The Document

To create a new Photoshop brush from the document, simply go up to the Edit menu at the top of the screen and choose Define Brush Preset from the list of options (depending on which version of Photoshop you're using, the option may be called simply Define Brush):

Go to Edit > Define Brush Preset.

Photoshop will pop open a dialog box asking you to give your new brush a name. I'm going to call mine "My New Brush". You'll probably want to choose a name that's a little more descriptive:

Name the new brush.

Click OK when you're done to close out of the dialog box, and that's all there is to it! We've successfully created a brand new custom brush in Photoshop that's ready and waiting to help us bring our creative vision to life. You can safely close out of the brush's document at this point.

To select the new brush any time you need it, first make sure you have the Brush Tool selected, then right-click (Win) / Control-click (Mac) anywhere inside your document to open the Brush Preset picker. Scroll down the list of available brushes until you see your brush thumbnail (newly created brushes will appear at the bottom of the list), then click on the thumbnail to select the brush. Press Enter (Win) / Return (Mac) once you've selected it to close out of the Brush Preset picker:

Select your new brush from the Brush Preset picker.

With the new brush selected, simply click and drag inside your document to paint a brush stroke:

The newly created brush in action.

It's a good start, but I think it's safe to say that at this stage, my new brush will be of limited use. Fortunately, now that we've created a brush tip, we can change and control how the brush behaves as we paint with it using Photoshop's Brush Dynamics, found in the main Brushes panel, which we'll take a quick look at next!

Step 7: Open The Brushes Panel

We've seen how to select a basic, ready-made brush using the Brush Preset picker, but if want more control over how our brush behaves, we need Photoshop's main Brushes panel, which gives us full access to some truly amazing options. We'll save our detailed look at the Brushes panel and all of its controls for another tutorial, but let's take a quick look at a few ways we can use it to alter the appearance of our brush strokes.

To open the Brushes panel, either go up to the Window menu at the top of the screen and choose Brushes from the list, or press the F5 key on your keyboard (press it again to close the panel), or click on the Brushes panel toggle icon in the Options Bar (click it again to close the panel):

The toggle icon in the Options Bar opens and closes the Brushes panel.

This opens the main Brushes panel, the big brother of the Brush Preset picker we saw earlier. By default when you first open the Brushes panel, the Brush Presets option is selected in the top left corner of the panel, which displays the same small brush icons along the right that we saw in the Brush Preset picker. To select a brush, simply click on its icon. Scroll down the list to your newly created brush and click on its icon to select it if it's not selected already. The very bottom of the Brushes panel displays a preview of what the brush stroke currently looks like. Since I haven't made any changes yet, the preview looks exactly the same as the brush stroke I painted a moment ago:

The main Brushes panel in Photoshop set to the Brush Presets option.

Step 8: Adjust The Brush Tip Spacing

Click on the words Brush Tip Shape directly below the Brush Presets option in the top left corner of the Brushes panel:

Click on the Brush Tip Shape option.

In the real world, if you were to paint with an actual brush, the brush would lay down a continuous coat of paint on the paper, but that's not how Photoshop works. Instead, Photoshop "stamps" the document with your brush tip as you drag your mouse. If the stamps appear close enough together, it creates the illusion of a seamless brush stroke, but if the stamps are spaced too far apart from each other, the individual stamps become obvious and the brush stroke appears ridged. Depending on the effect you're going for (like creating a dotted line, for example), you may want a lot of spacing between the stamps, but in most cases, a seamless brush stroke is more desirable.

With the Brush Tip Shape option selected in the Brushes panel, we can control the spacing between the stamps with the appropriately-named Spacing option at the very bottom of the panel. Spacing is controlled as a percentage of the width of your brush tip, and by default, it's set to 25%, which means that if the width of your brush tip is 100 pixels, Photoshop will lay down a new stamp every 25 pixels as you drag your mouse:

The Spacing option controls how frequently Photoshop "stamps" the brush tip as you paint.

For a smooth brush stroke, this default setting is usually too high. I'm going to lower mine down to around 13%. To lower the Spacing amount, either drag the slider towards the left or enter a specific value directly into the input box. You'll see the preview of the brush stroke updating to reflect the changes to the spacing:

Lower the Spacing amount for a smoother looking brush stroke.

Now, if I paint a stroke with my brush, it appears smoother because the individual stamps are closer together:

With the brush tip "stamps" being closer together, the stroke appears smoother.

Step 9: Select The Shape Dynamics Option

Click directly on the words Shape Dynamics below the Brush Tip Shape option we selected a moment ago, which gives us options for dynamically controlling the size, angle and roundness of the brush tip as we paint. Make sure you click on the words themselves. Clicking inside the checkbox to the left of words will turn the options on but won't give us access to their controls:

Click directly on the words "Shape Dynamics".

Step 10: Set The Angle Control To "Direction"

The main problem with the look of my brush stroke is that no matter which direction I paint in, those horizontal lines that make up my brush tip remain, well, horizontal. Let's fix that so the brush tip will follow the direction of my mouse cursor. With the Shape Dynamics option selected, change the Control option for the brush tip Angle to Direction. Again, you'll see the brush stroke preview at the bottom of the panel update to reflect the change:

Change the Control option for the Angle to "Direction".

I'll paint another stroke with my brush, and this time, things look much more natural. The brush tip is following the direction I'm painting in:

A more natural looking brush stroke.

Step 11: Set The Size Control To "Pen Pressure" (Requires Pen Tablet)

If you're using a pressure-sensitive pen tablet like I am, you can tell Photoshop that you want to control the size of the brush with your pen. With the Shape Dynamics options still selected, change the Control option for the brush tip Size to Pen Pressure:

Change the Control option for the Size of the brush to "Pen Pressure" (if you have a pen tablet, that is).

With the Pen Pressure option selected, I can easily control the size of the brush stroke on the fly, giving my custom brush an even more natural look:

The size of the brush can now be controlled dynamically with pen pressure.

Obviously, this is just a taste of the amount of control the Brushes panel gives us over the behavior of our brush, but in just a few short steps, we've managed to design and create a brand new custom Photoshop brush from scratch, and we've gotten a glimpse of how powerful the various dynamic brush controls in the Brushes panel really are. We'll cover the Brushes panel in much more detail in another tutorial.

And there we have it!