The Business End: Multi-User

Computer Systems

Multi-user computers are designed to serve groups of people all at a time,

from a small office to a huge international enterprise. Here are some types of

multi-user computers to be aware of:

✓ Server: A server is a computer that is dedicated to serving and support-

ing a group of network users and their information needs. There are dif-

ferent kinds of servers, varying greatly in size and power and performing

different functions. For example, a file server stores files in a central loca-

tion where multiple people can access them. A database server stores

a database, such as a product inventory, and allows users to look up

information in the database from their own computers. A print server

manages a group of shared printers, controlling and prioritizing print

jobs. Servers can be various sizes and designs. A tower server looks a lot

like a regular desktop computer (Figure 1-1). Rack servers are stacked in

multiples on storage racks, and accessed via a network interface rather

than having their own keyboards and monitors.

✓ Mainframe: A mainframe is a large, powerful computer capable of pro-

cessing and storing large amounts of business data. The main difference

between a mainframe and a server is that the mainframe functions as

the processing brain for multiple individual user terminals; it’s not just

a helper, but the primary processing device. For example, a mainframe

might run several dozen cash registers in a large department store.

✓ Supercomputer: A supercomputer is the largest and most powerful type

of computer. It can occupy a large room, or even an entire floor of a

building. Supercomputers are used when a job requires a huge amount

of processing power, such as molecular modeling, weather forecasting,

or cryptanalysis (code-breaking). They are found in high-tech academic,

government, and scientific research facilities.