4.2. Looking Inside the Box
Most of the processing and storage devices show up "inside the box." This section gives you a look at the major elements that you will find inside the system housing, or case.
The processor (also known as the central processing unit, or CPU) is the "brains of the organization," so to speak. It is designed to do very few things, but to do them extremely quickly. The processor performs a limited set of calculations based on requests from the operating system and controls access to system memory. Processor speed is measured in several different ways, including clock cycles or megahertz (MHz), and millions of instructions per second (MIPS). Any of these measures gives you an estimate of the processor's speed/power.
The speed of early processors ranged from 4 MHz to 8 MHz, but today's processors have broken the multigigahertz (GHz) mark. With the advent of multiple core processors, the processors speed is usually represented as a "per core" value.
4.2.2. Storage devices
Storage devices on your computer are responsible for storing data, such as the operating system, applications, and actual output of applications or user data. Depending on the amount and type of data, the five basic types of devices to work with are
Floppy drives, including some of the high-capacity formats ...