Glossary

Software created by people who are willing to give it away for the satisfaction of sharing or knowing they helped to simplify other people's lives. It may be free-standing software, or it may add functionality to existing software.

Like shareware, freeware is software you can download, pass around, and distribute without any initial payment. However, the great part about freeware is that you never have to pay for it. No 30 day limit, no demo versions, no disabled features -- it's totally free. Things like minor program updates and small games are commonly distributed as freeware. Though freeware does not cost anything, it is still copyrighted, so other people can't market the software as their own.

Frequency is the number times something occurs in a specific amount of time. In computing, frequency is used to measure processing speed, such as the clock speed of a CPU. For example, a 3.2 GHz processor has a frequency of 3.2 gigahertz, or 3,200,000,000 hertz. This means the processor performs 3,200,000,000 cycles each second. Since most instructions require multiple cycles, the number of instructions per second is typically less than the number of clock cycles. Therefore, MIPS, which measures instructions per second, is sometimes used to measure raw computing performance.

Frequency is also used to measure oscillation rates of waves within the electromagnetic spectrum. Some examples include radio waves, microwaves, visible light, and ultraviolet rays. FM radio broadcasts in the range of 87.5 to 108 megahertz. When you tune to 93.7, for example, you are instructing your radio to only receive signals that have an oscillation frequency of 93,700,000 hertz. Wi-Fi signals are broadcast at either 2.4 GHz or 5 GHz, both of which are much higher than the FM radio frequency band. The higher frequency prevents wireless interference and provides a stronger, more reliable signal over shorter distances.

File Transfer Protocol, a format and set of rules for transferring files from a host to a remote computer.

A gibibyte is a unit of data storage that equals 2 to the 30th power, or 1,073,741,824 bytes.

While a gigabyte can be estimated as 10^9 or 1,000,000,000 bytes, a gibibyte is defined as exactly 1,073,741,824 bytes. This helps avoid the ambiguity associated with the size of gigabytes. A gibibyte is 1,024 mebibytes and precedes the tebibyte unit of measurement.

The letters "GIF" actually stand for "Graphics Interchange Format," but you don't need to remember that. What you should know is that a GIF is a compressed image file format. GIF images use a compression formula originally developed by CompuServe (which is why you see the term "CompuServe GIF" in Photoshop, for those of you that care). GIFs are based on indexed colors, which is a palette of at most 256 colors. This helps greatly reduce their file size. These compressed image files can be quickly transmitted over a network or the Internet, which is why you often see them on Web pages. GIF files are great for small icons and animated images, but they lack the color range to be used for high-quality photos.

A gigabyte is 2 to the 30th power, or 1,073,741,824 bytes.

It can be estimated as 10 to the 9th power, or one billion (1,000,000,000) bytes. A gigabyte is 1,024 megabytes and precedes the terabyte unit of measurement. Hard drive sizes are typically measured in gigabytes, such as a 160GB or 250GB drive. The term gigabyte is often often abbreviated as simply a "gig" in speech. For example, if you have a 250GB hard drive, you could say, "I have 250 gigs of disk space." The prefix "giga" comes from the Greek word "gigas," meaning giant.

1024 megabytes.

One gigahertz is equal to 1,000 megahertz (MHz) or 1,000,000,000 Hz. It is commonly used to measure computer processing speeds. For many years, computer CPU speeds were measured in megahertz, but after personal computers eclipsed the 1,000 Mhz mark around the year 2000, gigahertz became the standard measurement unit. After all, it is easier to say "2.4 Gigahertz" than "2,400 Megahertz."

While gigahertz is most commonly used to measure processor speed, it can also measure the speed of other parts of the computer, such as the RAM and backside cache. The speed of these components, along with other parts of the computer, also impact the computer's overall performance. Therefore, when comparing computers, remember the number of gigahertz is not the only thing that matters.

Google is the world's most popular search engine. It began as a search project in 1996 by Larry Page and Sergey Brin, who were two Ph.D. students at Stanford University. They developed a search engine algorithm that ranked Web pages not just by content and keywords, but by how many other Web pages linked to each page. This strategy produced more useful results than other search engines, and led to a rapid increase in Google's Web search marketshare. The Google ranking algorithm was later named "PageRank" and was patented in September of 2001. In only a short time, Google became the number one search engine in the world.

According to Google's website, the company's mission is to "organize the world's information and make it universally accessible and useful." While the Web search remains Google's primary tool for helping users access information, the company offers several other services as well. Some of these include:

• Froogle - price comparison shopping
• Image Search - search for images on the Web
• Google Groups - online discussion forums
• Google Answers - answers to questions based on a bidding system
• Google Maps - maps and directions
• Google Toolbar - a downloadable search tool
• Blogger - a free blogging service
• Gmail - Web-based e-mail with several gigabytes of storage
• AdWords - Advertising services for advertisers
• AdSense - Advertising services for Web publishers

Google has become such a popular search engine that the term "Google" is now often used as a verb, synonymous with "search." For example, if you are looking for information about someone, you can Google that person using Google's search engine.

Computer graphics are images displayed on a computer screen. They can be either two or three-dimensional. Two-dimensional graphics come in raster or vector formats.

Raster graphics are the most common type of computer graphic and are used for icons, photos, and other basic images. Vector graphics are used for drawings, logos, and other scalable objects. 3D graphics are made up of polygons and can be created with CAD and 3D modeling programs. They are most commonly seen in video games and 3D animations.