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Chapter 4 Hardware, Software, and Mobile Systems
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Hardware Components
Over the course of your career, Every computer has a central processing unit (CPU), which is sometimes called “the brain”
application software, hardware, and of the computer. Although the design of the CPU has nothing in common with the anatomy of
firmware will change, sometimes animal brains, this description is helpful because the CPU does have the “smarts” of the machine.
rapidly. The Guide on pages 186–
187 challenges you to choose a The CPU selects instructions, processes them, performs arithmetic and logical comparisons, and
strategy for addressing this change. stores results of operations in memory. Some computers have two or more CPUs. A computer with
two CPUs is called a dual-processor computer. Quad-processor computers have four CPUs.
Some high-end computers have 16 or more CPUs.
CPUs vary in speed, function, and cost. Hardware vendors such as Intel, Advanced Micro Devices,
and National Semiconductor continually improve CPU speed and capabilities while reducing CPU
costs (as discussed under Moore’s Law in Chapter 1). Whether you or your department needs the
latest, greatest CPU depends on the nature of your work.
The CPU works in conjunction with main memory. The CPU reads data and instructions
from memory and then stores the results of computations in main memory. Main memory is some-
times called RAM, for random access memory.
All computers include storage hardware, which is used to save data and programs. Magnetic
disks (also called hard disks) are the most common storage device. Solid-state storage (aka an SSD
drive) is much faster than a hard drive and gaining in popularity, but it is several times more expen-
sive. USB flash drives are small, portable solid-state storage devices that can be used to back up data
and transfer it from one computer to another. Optical disks such as CDs and DVDs also are popular
portable storage media.

Types of Hardware

Figure 4-1 lists the basic types of hardware. Personal computers (PCs) are classic computing
devices that are used by individuals. In the past, PCs were the primary computer used in business.
Today, they are gradually being supplanted by tablets and other mobile devices. The Mac Pro is an
example of a modern PC. Apple brought tablets to prominence with the iPad. In 2012, Micro-
soft announced Surface and Google announced the Nexus series, all tablets. Smartphones are cell
phones with processing capability; the Samsung Galaxy S6 is a good example. Today, because it’s
hard to find a cell phone that isn’t “smart,” people often just call them phones.
A server is a computer that is designed to support processing requests from many remote
computers and users. A server is essentially a PC on steroids. A server differs from a PC prin-
cipally because of what it does. The relationship between PCs and servers is similar to the
relationship between clients and servers at a typical restaurant. Servers take requests from
clients and then bring them things. In restaurants this is food and silverware. In computing
environments servers can send Web pages, email, files, or data to PCs. PCs, tablets, and smart-
phones that access servers are called clients. As of 2016, a good example of a server is the Dell
PowerEdge server.

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Basic Types of Hardware