Browse the glossary using this index

Special | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | ALL

Page: (Previous)   1  2  3  4  5  6  7  8  9  10  ...  25  (Next)
  ALL

B

BIOS

Stands for "Basic Input/Output System." Most people don't need to ever mess with the BIOS on a computer, but it can be helpful to know what it is. The BIOS is a program pre-installed on Windows-based computers (not on Macs) that the computer uses to start up. The CPU accesses the BIOS even before the operating system is loaded. The BIOS then checks all your hardware connections and locates all your devices. If everything is OK, the BIOS loads the operating system into the computer's memory and finishes the boot-up process.

Since the BIOS manages the hard drives, it can't reside on one, and since it is available before the computer boots up, it can't live in the RAM. So where can this amazing, yet elusive BIOS be found? It is actually located in the ROM (Read-Only Memory) of the computer. More specifically, it resides in an eraseable programmable read-only memory (EPROM) chip. So, as soon as you turn your computer on, the CPU accesses the EPROM and gives control to the BIOS.

The BIOS also is used after the computer has booted up. It acts as an intermediary between the CPU and the I/O (input/output) devices. Because of the BIOS, your programs and your operating system don't have to know exact details (like hardware addresses) about the I/O devices attached to your PC. When device details change, only the BIOS needs to be updated. You can make these changes by entering the BIOS when your system starts up. To access the BIOS, hold down the DELETE or F2 key as soon as your computer begins to start up.


Bit

The smallest piece of computer information, either the number 0 or 1.

The computer term "bit" comes from the phrase "Binary DigIT," which is different than that thing you put around a horse's mouth. A bit is a single digit number in base-2 (a zero or a one) and is the smallest unit of computer data. A full page of text is composed of about 16,000 bits.

It is important not to confuse bits with bytes. Both are used to measure amounts of data, but it takes eight bits to make one byte. The most common area where bits are used intstead of bytes is in measuring bandwidth (in bits per second). Why? Probably because it makes your Internet connection sound faster than it really is.


Bitrate

Bitrate, as the name implies, describes the rate at which bits are transferred from one location to another. In other words, it measures how much data is transmitted in a given amount of time. Bitrate is commonly measured in bits per second (bps), kilobits per second (Kbps), or megabits per second (Mbps). For example, a DSL connection may be able to download data at 768 kbps, while a Firewire 800 connection can transfer data up to 800 Mbps.

Bitrate can also describe the quality of an audio or video file. For example, an MP3 audio file that is compressed at 192 Kbps will have a greater dynamic range and may sound slightly more clear than the same audio file compressed at 128 Kbps. This is because more bits are used to represent the audio data for each second of playback. Similarly, a video file that is compressed at 3000 Kbps will look better than the same file compressed at 1000 Kbps. Just like the quality of an image is measured in resolution, the quality of an audio or video file is measured by the bitrate.


BitTorrent

BitTorrent is a peer-to-peer (P2P) file sharing protocol designed to reduce the bandwidth required to transfer files. It does this by distributing file transfers across multiple systems, thereby lessening the average bandwidth used by each computer. For example, if a user begins downloading a movie file, the BitTorrent system will locate multiple computers with the same file and begin downloading the file from several computers at once. Since most ISPs offer much faster download speeds than upload speeds, downloading from multiple computers can significantly increase the file transfer rate.

In order to use the BitTorrent protocol, you need a BitTorrent client, which is a software program that accesses the BitTorrent network. The client program allows you to search for files and begin downloading torrents, which are in-progress downloads. Most BitTorrent clients allow you to resume torrents that have been paused or stopped. This can be especially helpful when downloading large files.

For a list of BitTorrent clients, view the .TORRENT file extension entry.


Blog

Short for "Web Log," this term refers to a list of journal entries posted on a Web page. Anybody who knows how to create and publish a Web page can publish their own blog. Some Web hosts have made it even easier by creating an interface where users can simply type a text entry and hit "publish" to publish their blog.

Because of the simplicity of creating a blog, many people (often young kids and adults) have found a new presence on the Web. Instead of writing confidential entries in a book that no one is supposed to see, people now can share their personal feelings and experiences with thousands of people around the world. Blogs are typically updated daily, monthly, or anywhere in between. "Blog" may also be used as a verb, as in "Wow, Matt sure blogged a lot last week."


Blu-ray

Blu-ray is an optical disc format such as CD and DVD. It was developed for recording and playing back high-definition (HD) video and for storing large amounts of data. While a CD can hold 700 MB of data and a basic DVD can hold 4.7 GB of data, a single Blu-ray disc can hold up to 25 GB of data. Even a double sided, dual layer DVD (which are not common) can only hold 17 GB of data. Dual-layer Blu-ray discs will be able to store 50 GB of data. That is equivalent to 4 hours of HDTV.

Blu-ray discs can hold more information than other optical media because of the blue lasers the drives use. The laser is actually blue-violet, but "Blu-ray" rolls off the tounge a little easier than "Blu-violet-ray." The blue-violet laser has a shorter wavelength than the red lasers used for CDs and DVDs (405nm compared to 650nm). This allows the laser to focus on a smaller area, which makes it possible to cram significantly more data on a disc the same size as a CD or DVD. Proponents of the Blu-ray format say they expect Blu-ray devices to replace VCRs (thank goodness) and DVD recorders as more people make the transition to HDTV. For the latest Blu-ray news, check out Blu-ray.com.


Bluetooth

This wireless technology enables communication between Bluetooth-compatible devices. It is used for short-range connections between desktop and laptop computers, PDAs (like the Palm Pilot or Handspring Visor), digital cameras, scanners, cellular phones, and printers.

Infrared once served the same purpose as Bluetooth, but it had a number of drawbacks. For example, if there was an object placed between the two communicating devices, the transmission would be interrupted. (You may have noticed this limitation when using a television remote control). Also, the Infrared-based communication was slow and devices were often incompatible with each other.

Bluetooth takes care of all these limitations. Because the technology is based on radio waves, there can be objects or even walls placed between the communicating devices and the connection won't be disrupted. Also, Bluetooth uses a standard 2.4 GHz frequency so that all Bluetooth-enabled devices will be compatible with each other. The only drawback of Bluetooth is that, because of its high frequency, its range is limited to 30 feet. While this is easily enough for transferring data within the same room, if you are walking in your back yard and want to transfer the address book from your cell phone to your computer in your basement, you might be out of luck. However, the short range can be seen as a positive aspect as well, since it adds to the security of Bluetooth communication.


BMP

Short for "Bitmap." It can be pronounced as "bump," "B-M-P," or simply a "bitmap image." The BMP format is a commonly used raster graphic format for saving image files. It was introduced on the Windows platform, but is now recognized by many programs on both Macs and PCs.

The BMP format stores color data for each pixel in the image without any compression. For example, a 10x10 pixel BMP image will include color data for 100 pixels. This method of storing image information allows for crisp, high-quality graphics, but also produces large file sizes. The JPEG and GIF formats are also bitmaps, but use image compression algorithms that can significantly decrease their file size. For this reason, JPEG and GIF images are used on the Web, while BMP images are often used for printable images.

File Extension: .BMP


Boolean

This is the logic that computers use to determine if a statement is true or false. There are 4 main boolean operators: AND, NOT, OR, and XOR. Below are some examples of how the 4 operators work:

x AND y returns True if both x and y are true, otherwise the expression returns False.

 

 

NOT x returns True if x is false (or null) and False if x is true.

 

 

x OR y returns True if either x or y or both are true; only if they are both false will it return False.

 

 

x XOR y returns True if either x or y are true, but not both. If x and y are both true or false, the statement will return False.

While boolean expressions are what drive the CPUs in computers, they can also be used by computer users. For example, when searching for information on the Web, many search engines accept boolean operators in the search phrases (i.e. "Yamaha AND piano NOT motorcycle"). Programmers often use boolean expressions in software development to control loops and variables as well.


Boot

When you boot a football, you kick it really far. When you boot a computer, you simply turn it on. Kicking your computer really far is not recommended, though you may be tempted to do so at times. The term "boot" comes from the word "bootstraps," which people at one time used to get their boots on. Likewise, "booting" a computer gets it up and running.

In simple terms, to boot a computer is to turn it on. Once the computer's power is turned on, the "boot process" takes place. This process involves loading the startup instructions from the computer's ROM, followed by loading the operating system from the current boot disk. The boot disk is usually an internal hard drive, but can also be an external drive, a CD or DVD-ROM, or even a floppy disk. Once the operating system software is loaded, the boot process is complete and the computer is ready to be used.



Page: (Previous)   1  2  3  4  5  6  7  8  9  10  ...  25  (Next)
  ALL