Copyright Goodheart-Willcox Co., Inc.
8 Introduction to Microsoft Offi fice
it to commit fraud, which is a form of theft. Computer viruses and other
malware can also be transmitted by Internet-based communication.
Categories of Computers
Historically, computers were grouped in one of three categories based
on size: mainframes, minicomputers, or microcomputers. A mainframe
is a very large high-processing computer that is used for big computing
needs. A minicomputer is a computer of midrange size and performance
between a microcomputer and a mainframe. A microcomputer is a
computer based on a microchip for the CPU.
The distinctions between the historical categories have become
blurred so much that the term minicomputer is rarely used today. This
is because the capability of microcomputers, smallest of the three, has
signifi expanded. Today, computers are usually categorized based ficantly
on usage and cost as well as size:
• supercomputers
• mainframes
• servers
• personal computers and mobile devices
Note that these are the categories of computers, which should not be
confused with the four phases of the digital revolution.
Supercomputers
Supercomputers have processing power that can handle complex
jobs beyond the scope of other computer systems. Supercomputers are the
fastest computers. Examples of projects undertaken by supercomputers
include breaking codes, molecular modeling, atmospheric modeling,
and climate predicting. The tasks analyze enormous amounts of data.
Supercomputers can be used to simulate global weather patterns, results
from earthquakes, and consequences from nuclear explosions. Scientists
and engineers are the primary users of supercomputers.
The speed of supercomputers is usually measured in fl oating point fl
operations per second (FLOPS). Floating point means numbers containing
decimal point fractions. Figure 1-5 shows the constantly increased
capability of supercomputers over the years.
Mainframes
Mainframe computers provide centralized storage, processing, and
overall management of large amounts of data. While supercomputers are
used for crunching data and numbers, mainframes are used to process
and store business transactions. The speed of mainframes is measured in
millions of instructions per second (MIPS).
Servers
A server is a special type of computer found on a network. A server
stores data and responds when requested by other computers in the
network. It allows other computers on the network to share programs and
FYI
There are many ways
to classify computers.
Other classifi or fications
applications include
the SETI project,
ROCKS clusters and
cluster computing, and
the DWave quantum
computer.
Computer Ethics
While you are at work or
school, it is important to
be respectful in your use
of computer equipment.
The computer is available
for your use as a tool for
research or to accomplish
a task. It is unethical
to use the computer to
download copyrighted
material or harass others.
Ethics