When most of us think of computers, we think of a Personal Computer, or PC, basically a home or work computer designed for an individual user. Today, computers come in all sizes - from ultra-portable smartphones that can slip into a purse to ultra-powerful, expandable desktops with screens the size of some TVs.

Consumers use computers for everything from staying in touch with friends on social networks to storing photos to reading books. And computer manufacturers have kept up with them, designing computers large and small to meet their every need. Desktop PCs, laptops, netbooks, tablets and smartphones are all computers and all serve different purposes.

A computer is simply a programmable machine. No matter the size, computers all have the same basic components:

  • The Central Processing Unit, or CPU, known as the brain of the computer. The CPU is housed in the processor. The processor executes commands and impacts a computer's speed. Look for information about who manufacturers a computer's processing chip and how fast it runs on the packaging.
  • Memory is where the processor stores and retrieves program instructions. It plays a role in how fast a computer runs and what a consumer can store on it.
    • The Hard Disk Drive is the part of memory that stores permanent information in the form of files. It's used primarily in Desktop computers and Laptops. The size of the hard drive determines how many files a computer can store.
    • Flash Memory is commonly used in smartphones, tablets, netbooks and some laptops and PCs instead of a hard drive. A Flash chip stores memory even when the power source is turned off. It accesses memory faster than a hard drive, but doesn't have as much storage capacity.