Page 154 -

Figure 4-2 Q4-1 What Do Business Professionals Need to Know About Computer Hardware? 153
Server Farm
Source: © Andrew Twort/Alamy

Finally, a server farm is a collection of, typically, thousands of servers. (See Figure 4-2.)
Server farms are often placed in large truck trailers that hold 5,000 servers or more. Typically
a trailer has two large cables coming out of it; one is for power, and the other is for data com-
munications. The operator of the farm backs a trailer into a pre-prepared slab (in a warehouse
or sometimes out in the open air), plugs in the power and communications cables, and, voilà,
thousands of servers are up and running!
Increasingly, server infrastructure is delivered as a service via the Internet that is often referred
to as the cloud. We will discuss cloud computing in Chapter 6, after you have some knowledge of
data communications.
The capacities of computer hardware are specified according to data units, which we discuss
next.

Computer Data

Computers represent data using binary digits, called bits. A bit is either a zero or a one. Bits are
used for computer data because they are easy to represent physically, as illustrated in Figure 4-3. A
switch can be either closed or open. A computer can be designed so that an open switch represents

# .KIJV UYKVEJGU TGRTGUGPVKPI $ &KTGEVKQP QH OCIPGVKUO TGRTGUGPVKPI

Figure 4-3
Bits Are Easy to Represent
Physically % 4GHNGEVKQP PQ TGHNGEVKQP TGRTGUGPVKPI