|
|
|
|
|
caldera
|
|
|
|
|
100BaseT
|
Another term for fast Ethernet, an upgraded standard for connecting computers into a local area network (LAN). 100BaseT Ethernet works just like regular Ethernet except that it can transfer data at a peak rate of 100 mbps. It's also more expensive and less common than its slower 10BaseT sibling.
|
|
10BaseT
|
The most common form of Ethernet is called 10BaseT, which denotes a peak transmission speed of 10 mbps using copper twisted-pair cable. Ethernet is a standard for connecting computers into a local area network (LAN).
|
|
16-bit
|
Refers to Microsoft® Windows™ 3.x.
|
|
32-bit
|
Refers to Windows 95/98/2K and Windows NT (3.51 and above).
|
|
3D API
|
3D Application Programming Interface. This generic term refers to any API that supports the creation of standard 3D objects, lights, cameras, perspectives, and so on. Such APIs include Argonaut's BRender and Microsoft's Reality Lab.
|
|
3D Sound
|
When we hear things in the physical world, our ears pick up a variety of audible clues that tell us such things as "a truck is approaching me rapidly, from behind and to the left, and it's remarkably near." Until recently, however, most computer-generated sound was merely stereophonic--sounds could appear from the left or right, but they had no real depth.
|
|
5.1
|
Digital surround sound is recorded on six separate tracks: front left, front right, front center, rear left, and rear right, with an extra track reserved for very low bass. Although analog surround sound (Dolby Pro Logic) also often uses six speakers, the analog format simply splits a traditional stereo signal into front and rear components.
|
|
64QAM
|
64-state Quadrature Amplitude Modulation. This digital frequency modulation technique is primarily used for sending data downstream over a coaxial cable network. 64QAM is very efficient, supporting up to 28-mbps peak transfer rates over a single 6-MHz channel. But 64QAM's susceptibility to interfering signals makes it ill suited to noisy upstream transmissions (from the cable subscriber to the Internet).
|
|
AA
|
Auto Answer. A modem indicator light that tells you the modem is ready to pick up the phone, so long as there's a communication program running and prepared to handle the call. The light is often not shining even when the modem is prepared to take a call, so it's not a useful light.
|
|
AC-3 (Dolby Digital)
|
This digital surround-sound format for home audio is called Dolby Digital in theaters. It is a 5.1 format, with six separate audio tracks. AC-3 has been chosen as the official sound format for digital TV, and is already encoded on many DVDs and Laserdiscs.
|
|
ACK
|
Acknowledgement. When a modem receives a data packet, it sends a signal back to the sending modem. If all the data is present and correct, it sends an ACK (acknowledgement) signal, which acts as a request for the next data packet. If the modem didn't get all the data, it sends back a negative acknowledgement, or NAK.
|
|
ACPI
|
Advanced Configuration and Power Interface. This power management standard, proposed by Microsoft, Intel, and Toshiba, lets the PC control power to peripherals like CD-ROMs and printers, as well as consumer devices hooked up to the PC. Peripherals can also use ACPI to turn on the PC. For example: you could insert a CD-ROM into a drive, and the computer would automatically boot up.
|
|
Active Channels
|
An Active Channel is what Microsoft calls a Web site that has been enabled for push delivery to Internet Explorer 4.0 browsers. To create a channel, developers write and upload a CDF (channel definition format) file to their Web site; new content is delivered to users automatically when the site is updated. Developers and subscribers can control the update frequency; which channels, subchannels, and items (sections) are subscribed to; and other channel characteristics. Most Active Channels use dynamic HTML (DHTML) and other effects to spice up content and make it more interactive.
|
|
Active Matrix
|
Flat-panel displays for laptop computers are created by laying diodes over a superfine grid of wires. The diodes are activated by applying current to various points around the grid. Connect enough of these dots and you get an image. Active-matrix displays use transistors to keep their diodes in an on or off state, unlike their passive-matrix cousins, which rely on the diodes' persistence. As a result, active-matrix displays are brighter and produce better color than passive-matrix displays. However, the additional technology required to build active displays also makes them far more expensive.
|
|
ActiveX Control
|
An ActiveX control is a component program object that can be re-used by many application programs within a computer or among computers in a network. An ActiveX control can be created in any programming language that recognizes Microsoft's Component Object Model (COM).
|
|
ADO
|
ActiveX Data Objects. A Microsoft technology that provides a unified way to access different data sources with a single data model. By providing a single data model, ADO lets you access data in the same way whether it exists in a database, a spreadsheet, and even text files.
|
|
ADSL
|
Asymmetric Digital Subscriber Line. Like ISDN, ADSL uses standard phone lines to deliver high-speed data communications. But while ISDN's transmission speed is limited to 64 kbps, ADSL technology can deliver upstream (from the user) speeds of 640 kbps and downstream (to the user) speeds of more than 6 mbps. Even better, ADSL uses the portion of a phone line's bandwidth not utilized by voice, allowing for simultaneous voice and data transmission.
|
|
AGP
|
Accelerated Graphics Port. A dedicated graphics bus slot on PC motherboards. Designed by Intel, AGP operates at 66 MHz and transfers data at a rate up to 528 MB/sec. By comparison, the PCI slot that most graphics cards currently use runs at 33 MHz and has a maximum transfer rate of 132 MB/sec.
|
|
Alpha Blending
|
In computer graphics, each pixel has three channels of color information--red, green, and blue--and sometimes a fourth called the alpha channel. This channel controls the way in which other graphics information is displayed, such as levels of transparency or opacity. Alpha blending is the name for this type of control, and it's used to simulate effects such as placing a piece of glass in front of an object so that the object is completely visible behind the glass, unviewable, or something in between.
|
|
Alpha Channel
|
In computer graphics, each pixel has three channels of color information--red, green, and blue--in various bit depths. In 24-bit display graphics adapters, there are 8 bits per color per pixel, but when the card has a 32-bit bus, the additional 8 bits are used as an alpha channel to control the color information of the other 24 bits of color.
|
|
Amplitude
|
Like any wave, analog signals contain peaks and valleys. By measuring the difference between the peaks and the valleys and then dividing by a factor of two, we get the amplitude--or strength--of the wave. The larger the amplitude, the stronger the wave.
|
|
AMPS
|
Advances Mobile Phone Service. Analog cellular radio standard and the foundation of the cellular industry in the United States.
|
|
