2D stands for two dimensional. This is commonly used to describe the display
mode of a video card when it is not in
3D
mode. Most programs like word processors, web browsers, and the operating
system user interface operate in 2D mode although some with advanced user
interfaces may operate in 3D mode. Programs like many games and many
visualization programs operate in 3D mode.
3D stands for three dimensional. This is commonly used to describe the
display mode of a video card when it is displaying three dimensional objects
as in many games, engineering, and three dimensional artwork programs. Most
operating systems currently (2006) operate in
2D
mode but some newer ones are starting to support 3D user interfaces.
A kind of
expansion slot. AGP stands for accelerated graphics port. It is a faster version of
PCI which was designed to speed up
video card data
transfers. Newer computers use the faster and more flexible
PCI-Express x16
slots for video cards.
In the context of computers, analog is a method of representing data with a
continuous range of values. An analog voltage varies between minimum and
maximum values to represent the datum. For example, a VGA monitor uses an
analog voltage to represent the brightness of a color component which makes
up an image. Most things inside a computer are
digital
rather than analog. Analog values are not commonly used. Analog is used for
controlling things like the image on a
CRT
monitor or a sound being generated through speakers. But even in those cases,
most of the computer's handling of those signals is done digitally and is
converted to analog just before driving the monitor or speaker. When analog
data is sent through a cable, the accuracy of the data is degraded to some
extent. The data degrades even when sent through high-quality shielded
cables. This is as opposed to digital transmission where the data (barring
serious problems) received is identical to the data transmitted.
BIOS is short for Basic Input Output System. Your BIOS is a program which
controls the basic functionality of various pieces of hardware in your
computer.
Motherboard
BIOSes let you change things like the speed of your
RAM, the
speed of your
AGP
port, how your
expansion slots
work, etc. You can find basic information about motherboard BIOSes
here.
Video cards
also have BIOSes.
Bit is short for binary digit. It is the smallest unit of storage in a
computer. It has two possible values: 0, and 1. Computers use bits to keep
track of things. Since a bit can only store two values you have to group a
bunch of bits together to store larger numbers of values. For example, a
byte
is made up of eight bits and can store all the integers between 0 and 255.
Computers have a lot of storage these days so you're more likely to run into
things like
megabytes
and
gigabytes.
Boot is short for
bootstrap.
Bootstrapping refers to the process of loading and starting an operating
system. It's derived from the phrase "pulling yourself up by your
bootstraps". It is often called "boot" for short. A cold boot is a bootstrap
which happens immediately after the computer has been turned on. A warm boot
is one which happens when the operating system restarts without turning the
computer off.
A byte is made up of eight
bits.
A byte is large enough to contain all integers between 0 and 255. Bytes are
the standard unit of storage used in computers. Modern computers tend to have
lots of bytes of
RAM,
hard disk space, etc. so amounts of storage tend to be given in
megabytes
or
gigabytes.
A cache is a small amount of high-speed memory which keeps a copy of data
which is stored in lower-speed memory. A cache holds copies of the most
commonly accessed data. When the data needs to be accessed, it uses the
speedy cache if possible and only uses the slower memory if the data is not
in the cache. As a result, accessing cached data is sped up substantially. A
CPU
has a cache which has copies of some of the data kept in the
motherboard
RAM.
Most CPUs actually have at least two caches: the primary cache (L1 cache or
level 1 cache) is the fastest and the secondary cache (L2 cache or level 2
cache) is slower and usually much larger. When the CPU accesses data, it
accesses the data in the primary cache if possible. If it's not in the
primary cache then it tries the secondary cache. If it's not in either of the
caches then it must access the much slower motherboard RAM.
CPU stands for central processing unit. This is the main silicon chip on the
motherboard
which does the general purpose processing for the computer. Most CPUs in PCs
are made by Intel or AMD.
CRT stands for cathode ray tube. CRT computer monitors are the older style
ones which use TV-type tubes to display images. CRTs are large, heavy, and
consume a lot of power compared to
LCD
monitors. CRT monitors can display reasonably sharp images at many
screen resolutions.
LCD monitors are perfectly sharp only at their native resolution (or their
native resolutions divided by 2, 3, etc.) and display other resolutions
relatively poorly.
DDR is short for double data rate. Synchronous memory chips operate at a
given clock rate. Single data rate memory can access one value per clock. So
a 100 MHz single data rate memory chip has a peak data access rate of 100
million accesses per second. DDR memory can access two values per clock. So a
100 MHz DDR memory chip has a peak data access rate of 200 million accesses
per second. Other common forms of DDR memory are DDR-II and GDDR3. They have
different technical specifications than plain DDR but they also access two
values per clock.
A device driver is a software which allows access to a piece of hardware. For
example, you must install a printer's device driver for the operating system
to be able to use the printer.
In the context of computers, digital is a method of representing data with a
discrete range of values. This is as opposed to
analog
which represents data with a continuous range of values. Most things inside
a computer are digital rather than analog. Analog values are not commonly
used. Analog is used for controlling things like the image on a
CRT
monitor or a sound being generated through speakers. But even in those cases,
most of the computer's handling of those signals is done digitally and is
converted to analog just before driving the monitor or speaker. Data
transmitted through a cable digitally (barring serious problems) loses no
accuracy. The received data is identical to the transmitted data. Analog
transmission, on the other hand, suffers some degradation when going through
the cable.
A display adapter is hardware which displays images on your monitor. The term
"display adapter" can refer to both
video cards and
integrated graphics.
A display driver is software which allows other programs to access and use a
display adapter. You
must have a display driver installed in order for your display adapter to do
anything other than the most basic operations. Most operating systems have a
default display driver which will work for most display adapters but has
limited functionality. In order to use the more advanced features like three
dimensional graphics, a full display driver designed for that specific
display adapter must be installed.
Driver is short for
device driver.
DVI is a
digital
video standard introduced in 1999. DVI stands for Digital Visual Interface.
DVI is in the process of replacing
VGA
as the most common way to connect monitors to computers. DVI was created to
provide a standard way to transfer an image in digital form rather than in
the
analog
form used by VGA. DVI is used almost exclusively in
LCD
panels.
CRTs
which accept DVI digital inputs are extremely rare. The CRTs which support
DVI are usually high-end monitors which are trying to avoid image quality
degradation in the VGA cable by transmitting the data digitally. The DVI
connector also optionally supports analog video signals.
There is more information about DVI on
this page.
EDID stands for extended display identification data. When a
video card
wants to know about the capabilities of a monitor, it reads the EDID from the
monitor. The EDID data contains information like the
resolution
and
refresh rate
of supported screen modes. It also tells whether the monitor is digital or
analog as well as many other details about the monitor.
A card which plugs into an
expansion slot on the motherboard to add a device to the computer. Expansion cards
can be things like
video cards,
network boards, sound cards, etc.
A connector on the motherboard which accepts an
expansion card to add a device to the computer. The most common kinds of expansion
slots are
AGP,
PCI,
and
PCI-Express.
GB/s stands for
gigabytes
per second. A
gigabyte
is approximately a billion bytes
(actually it's 1,073,741,824 bytes). So 1 GB/s is about a billion bytes per second.
GHz is short for gigahertz. A gigahertz is a billion (1,000,000,000) cycles
per second. Various clock rates in a computer are measured in gigahertz. For
example, a 3.2 GHz
CPU
runs at 3.2 billion (3,200,000,000) cycles per second.
A gigabyte is little more than a billion bytes (actually it's 1,073,741,824
bytes). The size of hard disks are often given in gigabytes.
GPU stands for graphics processing unit. This is the silicon chip on a
display adapter which
does the graphics calculations. Most of the GPUs are currently made by Intel,
NVIDIA, or ATI. Other manufacturers include VIA, SiS, and Matrox.
Graphics driver is the same as
display driver.
Hz is short for hertz. Hertz is the unit for cycles per second. For example,
a video monitor with a
screen refresh rate
of 75 Hz refreshes the screen 75 times a second.
Integrated graphics means that the hardware which displays images on the
monitor is integrated into the
motherboard.
It's built into the motherboard in order to lower costs. Integrated graphics
also tends to be slower than
video cards and
have less advanced functionality.
Integrated video means that the hardware which displays images on the
monitor is integrated into the
motherboard.
It's built into the motherboard in order to lower costs. Integrated video
also tends to be slower than
video cards and
have less advanced functionality.
LCD stands for liquid crystal display. LCD computer monitors are the newer
flat panel ones which use a flat LCD panel to display images. LCD panels are
smaller, lighter, and consume less power than
CRT
monitors. LCD monitors running at their native resolution (or their
native resolutions divided by 2, 3, etc.) display much sharper images than
CRT monitors but LCDs display images poorly at other resolutions.
LED stands for light emitting diode. An LED is a small solid-state light.
Most of the small lights on a computer are LEDs because they are cheap and
don't burn out.
A megabyte is little more than a million bytes (actually it's 1,048,576
bytes). The amount of
RAM
in a computer is often given in megabytes.
MB/s stands for
megabytes
per second. A
megabyte
is approximately a million bytes
(actually it's 1,048,576 bytes). So 1 MB/s is about a million bytes per second.
MHz is short for megahertz. A megahertz is a million (1,000,000) cycles per
second. Various clock rates in a computer are measured in megahertz. For
example, a 400 MHz
GPU
on a video card runs at 400 million (400,000,000) cycles per second.
This is the main circuit board in your computer. It holds the
CPU,
the main memory, and the expansion slots.
Setting the clock rate of a chip higher than its intended value is called
overclocking. This increases the speed of the chip but it also heats it up
and can cause stability problems. It may even shorten the lifespan of the
chip if it is overclocked too much. People overclock to make parts of their
computers run faster without having to buy the more expensive chips which
officially support the higher clock rates.
A kind of
expansion slot. PCI stands for peripheral component interconnect. PCI slots can be
used to add all kinds of devices to a computer including
video cards,
network boards, and disk controllers. PCI expansion slots cannot accept
PCI-Express
expansion cards.
A kind of
expansion slot. PCI-Express is a faster kind of slot than
PCI.
PCI-Express slots can be used to add all kinds of devices to a computer
including
video cards,
network boards, and disk controllers. There are different sizes of
PCI-Express expansion slots. PCI-Express x16 slots are used for video cards.
PCI-Express x1 slots are used for many different kinds of devices.
PCI-Express expansion slots cannot accept PCI
expansion cards.
This is the kind of
PCI-Express
expansion slot
which is usually used to hold
video cards.
The "x16" part refers to the number of lanes. This kind of slots has 16 lanes.
Each lane can read data at a peak of 250
MB/s
and write at 250
MB/s
simultaneously. As a result, a PCI-Express x16 slots can read at 4
GB/s
and write at 4
GB/s.
Pixel is short for picture element. You can make a pretty good version of an
image by creating a two dimensional array of small squares and storing a
single color in each square. Each of the small squares is a pixel. An image
with a resolution of 640 by 480 pixels is made up of 640 columns where each
column is 480 pixels tall. That image contains 640 times 480 pixels or
307,200 pixels. The more pixels that are in an image, the sharper it is. A
1280 by 960 version of an image has twice as many columns and twice as many
rows and looks much sharper than a 640 by 480 image.
RAM is just computer memory. Your computer contains lots of RAM chips where
it stores information. The main memory in your computer is probably stored
on memory sticks which contain 256MB or more apiece. Your video card also
contains RAM chips where it stores information used to draw images on your
monitor. RAM actually stands for random access memory but that's not
important for its current usage.
Rebooting a computer means that the computer shuts down and then
bootstraps
the operating system again. Rebooting is done after you've made a change
which requires restarting the operating system.
The screen image you see on a computer monitor is repeatedly redrawn many times
a second. The rate at which the entire screen image is redrawn is called the
screen refresh rate. It's generally expressed in cycles per second or hertz.
CRTs
display an image by shooting a beam of electrons at phospors on the front
surface of the CRT tube. The phospors glow for a little while after being hit by the
electrons. The phosphor image is bright after being drawn and then quickly
fades. If the CRT image is redrawn too slowly then the image flickers
noticeably. For a standard computer CRT, a 60 Hz refresh rate flickers badly
enough to cause eyestrain in most people. 75Hz barely flickers and 85Hz is
considered flicker free.
LCDs
display their screen image using a completely different technology which doesn't
flicker. There's still some benefit in increasing an LCDs refresh rate if you
want it to display quickly changing images as seen in many games. But, for the
most part, 60Hz is an acceptable refresh rate for LCDs.
The screen image displayed on a computer monitor is actually a two dimensional
array of
pixels.
The number of pixels used to display an image is called the screen resolution.
It is usually expressed as the number of horizontal pixels (the number of
columns of pixels) and the number of vertical pixels (the number of rows of
pixels). For example a screen resolution of 640 X 480 (pronounced "640 by 480")
is 640 pixels wide and 480 pixels tall. More pixels produce a sharper image so
an 800 X 600 screen resolution is sharper than 640 X 480.
Setting the clock rate of a chip lower than its intended value is called
underclocking. This makes the chip run cooler and slows it down. This is
usually down to try to troubleshoot problems. If underclocking solves a
problem, then it usually means the chip is damaged or overheating.
Unzipping is short for the process of uncompressing a file which has been
compressed with the ZIP compression method. Windows XP has built-in
zip file
decompression software. One way to unzip in XP is to right-click on the zip
file and then select "Extract All...". That allows you to select a
destination directory and then uncompress the file(s) into it. If the zip
file looks like a directory, then double-clicking on the zip file opens the
file up as a directory which allows access to the compressed file(s). You can
also use many free or shareware software utilities to compress and decompress
zip files.
WinZip and
WinRAR are two popular choices.
VGA is the long-used video standard which was introduced in 1987. VGA stands
for Video Graphics Array. VGA actually is the name of the main chip on the
original VGA
video card
introduced by IBM. Over time, VGA has become a more general
term refering to a particular video card standard which includes the VGA
output connector. The VGA connector is still commonly used but is in the
process of being supplanted by the newer
DVI connector.
The VGA connector is sometimes called an HD-15 connector or a DSub-15
connector.
There is more information about VGA on
this page.
Video board is the same as
video card
A video card is an
expansion card
which displays images on your monitor.
Video driver is the same as
display driver.
Video
RAM
refers to the memory chips on a video card. Current (2006) video cards
commonly have from 64MB to 512MB of video RAM.
A zip file is a file which has been compressed with the ZIP compression
method. Decompressing a zip file is refered to as
unzipping.
Windows XP has built-in
zip file
decompression software. One way to unzip in XP is to right-click on the zip
file and then select "Extract All...". That allows you to select a
destination directory and then uncompress the file(s) into it. If the zip
file looks like a directory, then double-clicking on the zip file opens the
file up as a directory which allows access to the compressed file(s). You can
also use many free or shareware software utilities to compress and decompress
zip files.
WinZip and
WinRAR are two popular choices.
link directory
