Computer Terms
Input Device - Touch Screen, Keyboard, Mouse, Microphone, Joystick
Output Device - Monitor, floppy drive, printer
Bit - Short for binary digit, the smallest unit of information on a machine.
Byte - Abbreviation for binary term, a unit of storage capable of holding
a single character. On almost all modern computers, a byte is equal to 8
bits.
Modem - Short for modulator-demodulator. A modem is a device or program
that enables a computer to transmit data over, for example, telephone or
cable lines. Computer information is stored digitally, whereas information
transmitted over telephone lines is transmitted in the form of analog
waves. A modem converts between these two forms.
CPU - list current Intel and Motorola options/platforms - Abbreviation of
central processing unit, and pronounced as separate letters. Sometimes
referred to simply as the processor or central processor, the CPU is where
most calculations take place. In terms of computing power, the CPU is the
most important element of a computer system.
Motorola: PowerPC architecture in 1994. -actually motorola's most recent
efforts have been on wireless phones and wireless networking.
Intel is currently working on their Pentium 4 with a FSB of 800MHz!
How fast is reasonable - anthing over 2Ghz is in the ballpark.
CISC -stands for complex instruction set computer in which the CPU
supports as many as two hundred instructions.
RISC - a type of microprocessor that recognizes a relatively limited
number of instructions. One advantage of reduced instruction set computers
is that they can execute their instructions very fast because the
instructions are so simple.
ALU - arithmetic logic unit, the part of a computer that performs all
arithmetic computations, such as addition and multiplication, and all
comparison operations. The ALU is one component of the CPU (central
processing unit).
Control Unit - wow, this term is way too vague.
ROM - read-only memory, computer memory on which data has been prerecorded.
Cache - a special high-speed storage mechanism. It can be either a
reserved section of main memory or an independent high-speed storage
device. Two types of caching are commonly used in personal computers:
memory caching and disk caching.
RAM - How much = 256MB+ random access memory, a type of computer memory
that can be accessed randomly; that is, any byte of memory can be accessed
without touching the preceding bytes.
SDRAM - Synchronous DRAM, a type of DRAM that can run at much higher clock
speeds than conventional memory. SDRAM actually synchronizes itself with
the CPU's bus and is capable of running at 133 MHz, about three times
faster than conventional FPM RAM, and about twice as fast EDO DRAM and
BEDO DRAM.
SGRAM - Synchronous Graphic Random Access Memory, a type of DRAM used
increasingly on video adapters and graphics accelerators. Like SDRAM,
SGRAM can synchronize itself with the CPU bus clock up to speeds of 100
MHz. In addition, SGRAM uses several other techniques, such as masked
writes and block writes, to increase bandwidth for graphics-intensive
functions.
VRAM - video RAM, and pronounced vee-ram. VRAM is special-purpose memory
used by video adapters. Unlike conventional RAM, VRAM can be accessed by
two different devices simultaneously. This enables the RAMDAC to access
the VRAM for screen updates at the same time that the video processor
provides new data. VRAM yields better graphics performance but is more
expensive than normal RAM.
EDO RAM - Extended Data Out Dynamic Random Access Memory, a type of DRAM
that is faster than conventional DRAM. Unlike conventional DRAM which can
only access one block of data at a time, EDO RAM can start fetching the
next block of memory at the same time that it sends the previous block to
the CPU.
BUS - A collection of wires through which data is transmitted from one
part of a computer to another.
BIOS - basic input/output system, the built-in software that determines
what a computer can do without accessing programs from a disk.
SCSI - small computer system interface, a parallel interface standard used
by Apple Macintosh computers, PCs, and many UNIX systems for attaching
peripheral devices to computers. SCSI interfaces provide for faster data
transmission rates (up to 80 megabytes per second) than standard serial
and parallel ports. In addition, you can attach many devices to a single
SCSI port, so that SCSI is really an I/O bus rather than simply an
interface.
USB - Universal Serial Bus, an external bus standard that supports data
transfer rates of 12 Mbps. A single USB port can be used to connect up to
127 peripheral devices, such as mice, modems, and keyboards. USB also
supports Plug-and-Play installation and hot plugging.
PCI - Peripheral Component Interconnect, a local bus standard developed by
Intel Corporation.
Active Matrix Display (TFT) - thin film transistor, a type of LCD
flat-panel display screen, in which each pixel is controlled by from one
to four transistors. The TFT technology provides the best resolution of
all the flat-panel techniques, but it is also the most expensive. TFT
screens are sometimes called active-matrix LCDs.
Pixel - Picture Element, a pixel is a single point in a graphic image.
CGA - pixel dimensions - color/graphics adapter, an old graphics system
for PCs. 640 by 200
EGA - pixel dimensions - enhanced graphics adapter, a graphics display
system for PCs introduced by IBM in 1984. EGA supports 16 colors from a
palette of 64 and provides a resolution of 640 by 350. This is better than
CGA but not as good as VGA. EGA is now obsolete.
VGA - pixel dimensions - video graphics array, a graphics display system
for PCs developed by IBM. VGA has become one of the de facto standards for
PCs. In text mode, VGA systems provide a resolution of 720 by 400 pixels.
In graphics mode, the resolution is either 640 by 480 (with 16 colors) or
320 by 200 (with 256 colors). The total palette of colors is 262,144.
XGA - pixel dimensions - extended graphics array, a high-resolution
graphics standard introduced by IBM in 1990. XGA was designed to replace
the older 8514/A video standard. It provides the same resolutions (640 by
480 or 1024 by 768 pixels), but supports more simultaneous colors (65
thousand compared to 8514/A's 256 colors). In addition, XGA allows
monitors to be non-interlaced.
Hard Drives - capacity & speed & function if possible - A magnetic disk
on
which you can store computer data, usually a 12ms seek time, with
capacities of over 100GB available.
DVD - capacity & speed & function if possible digital versatile disc
or
digital video disc, a type of optical disk technology similar to the
CD-ROM. A DVD holds a minimum of 4.7GB of data, enough for a full-length
movie. DVDs are commonly used as a medium for digital representation of
movies and other multimedia presentations that combine sound with
graphics.
The DVD specification supports disks with capacities of from 4.7GB to 17GB
and access rates of 600KBps to 1.3 MBps. One of the best features of DVD
drives is that they are backward-compatible with CD-ROMs, meaning they can
play old CD-ROMs, CD-I disks, and video CDs, as well as new DVD-ROMs.
Newer DVD players can also read CD-R disks.
CD-ROM - capacity & speed & function if possible - Compact Disc-Read-Only
Memory, a type of optical disk capable of storing large amounts of data --
up to 1GB, although the most common size is 650MB (megabytes). A single
CD-ROM has the storage capacity of 700 floppy disks, enough memory to
store about 300,000 text pages.
CDRW-ROM - capacity & speed & function if possible - CD-ReWritable disk,
a
type of CD disk that enables you to write onto it in multiple sessions.
One of the problems with CD-R disks is that you can only write to them
once. With CD-RW drives and disks, you can treat the optical disk just
like a floppy or hard disk, writing data onto it multiple times.
Zip Drive - capacity & speed & function if possible high-capacity floppy
disk drive developed by Iomega Corporation. Zip disks are slightly larger
than conventional floppy disks, and about twice as thick. They can hold
100 or 250 MB of data. Because they're relatively inexpensive and durable,
they have become a popular media for backing up hard disks and for
transporting large files.
Super Drive - capacity & speed & function if possible - SuperDisk is
the
high-capacity floppy disk standard, 12 megabits-per-second USB interface.
120 or 250MB versions. http://www.itreviews.co.uk/hardware/h97.htm
Jaz Drive - capacity & speed & function if possible 1-2G capacity,
7.35MB/Sec, 10ms seek time - another drive type, usually used for backups
since not many machines have this drive type.
WORM Memory - capacity & speed & function if possible write once, read
many, an optical disk technology that allows you to write data onto a disk
just once. After that, the data is permanent and can be read any number of
times. AKA CD-R
Unlike CD-ROMs, there is no single standard for WORM disks, which means
that they can only be read by the same type of drive that wrote them. This
has hampered their acceptance, although they have found a niche market as
an archival media.
Tape Drive - capacity & speed & function if possible -A device, like
a
tape recorder, that reads data from and writes it onto a tape. Tape drives
have data capacities of anywhere from a few hundred kilobytes to several
gigabytes. Their transfer speeds also vary considerably. Fast tape drives
can transfer as much as 20MB (megabytes) per second. The disadvantage of
tape drives is that they are sequential-access devices, which means that
to read any particular block of data, you need to read all the preceding
blocks. This makes them much too slow for general-purpose storage
operations. However, they are the least expensive media for making
backups.
Floppy Drive - capacity & speed & function if possible - a disk drive
that
can read and write to floppy disks. Standard floppy drives have a 1.44 MB
capacity, although several variations are available. These are among the
slowest drives available and were the standard way to move documents from
machine to machine. They are being replaced by USB drives, CDRs and the
internet as the primary means of moving files between computers.
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6420 Assignments - Computer Use in the Classroom
updated 7-14-05 by Simon Goble