Introduction to Personal Computers

What is a computer?

com·put·er (kem-py¡¹ter) noun

1. A device that computes, especially a programmable electronic machine that performs high-speed mathematical or logical operations or that assembles, stores, correlates, or otherwise processes information.

These days, computers are everywhere. According to the above definition from the American Heritage Dictionary, computers include your VCR, your car, your fax machine, even your watch and programmable coffee maker. At the other end of the scale are multi-user mainframe computers, minicomputers, and high-end specialized workstations. We will be talking about certain personal computers, also known as microcomputers or PCs, which are "for use by an individual, as in an office or at home or school."

Personal computers are for a single user. They generally have a monitor, keyboard, and pointing device such as a mouse. The two most popular types are MacIntosh or PC.

Basic terms and concepts

There is a huge and intimidating specialized computer vocabulary. Most computer users get along just fine knowing only a few key terms. Here are some of the basic terms and concepts which will really help you in learning about and understanding computers.

Important concepts

	Computers work with Digital information in bits. Any information which can be encoded or described with some scheme of words or numbers can be stored and manipulated digitally.
	Bytes, kilobytes (KB), megabytes (MB), gigabytes (GB) are the basic units in which digital information is stored and measured. A single byte consists of 8 bits and can be thought of as one character (a letter or number).
	Hardware is the physical metal and plastic of a computer, sort of like your body is to you.
	Software is the programs which tell the computer what to do, sort of like the skills and knowledge that you can learn from a teacher or how-to book.

Personal Computer Hardware

Note: Memory (RAM) and hard disk space are both measured in bytes, so it is easy to confuse the two. But they serve very different functions. RAM is fast, small, expensive, and temporary. Disk space is comparatively slow, large, cheap, and permanent. RAM is used by the microprocessor as its working space. Files are stored on hard disks.

Files

Files are the basic unit in which bytes of information are organized on disks. Special types of files are programs and folders. Programs are instructions that computers can carry out. Folders (also called directories) are files that can contain other files and folders.

See Using Electronic Files for basic information on how to work with files.

Software

Software or programs are instructions that tell a computer what to do. An operating system (OS) is the software that is automatically loaded when a computer starts up, and it controls the overall behavior of the computer. While the computer is on, the OS is always running. Other programs (applications) use the operating system to provide basic services. We will be talking about Windows (for IBM-compatible PCs) and the Mac OS (for MacIntosh-compatibles). Both provide Graphical User Interfaces (GUIs). There are other OS, including DOS. There are many versions of each type of OS. We will focus on elements common to all GUIs.

	Mice, pointers, cursors, clicking, double-clicking, dragging and dropping
	Desktop, Icons
	Windows and their parts -- title bar, menu bar, control boxes
	Dialog boxes, buttons

What do computers do?

Applications (programs)

Applications are programs that allow the user to actually accomplish work on the computer. They instruct the computer to do specific tasks with a certain end in mind. Examples of common types of applications include word processing, spreadsheets, databases, communication programs, and games. Applications have certain system requirements (operating system and hardware). Popular applications often have different versions for different operating systems. Some basic applications are included with Windows or the Mac OS or bundled with new computers, but you will probably want to purchase additional programs.

Applications are started or launched in a variety of ways, depending on the operating system. More than one application can be running at a time, and you can switch between them.

Types of Personal Computers

When most people talk about personal computers they mean either IBM-compatible PCs or MacIntosh PCs. Those are the personal computers which account for over 95% of the home, school, and business markets, and that's what we'll be talking about tonight. We will ignore the many other varieties of personal computers such as those made by Atari and Amiga. We also will not be talking about personal digital assistants (PDAs) and high-end workstations such as those manufactured by Sun, Intergraph, Digital, and Silicon Graphics.

Buying a computer

Purchasing a computer is a daunting task. Here are some hints for how to proceed.

Know your needs.

What will you be using it for? Word processing and communications requirements are different than sophisticated multi-media and cutting-edge simulation games.

Mac or PC?

Both types of machines work well.

	PCs are by far the most common personal computers, so more people are familiar with them and the widest selection of hardware and software is available.
	Some maintain that the Macs are still easier to use. Through the use of expensive emulation software, your Mac can run PC software.

Deciphering the terminology

We'll look at some typically terse and cryptic computer specifications and discuss what they mean and what is important.

Computer Purchasing Recommendations

Here are my general recommendations for purchasing a personal computer today (October, 2000). I assume you will want to write letters, get on the Internet, and maybe do some basic graphics, but you don't have any unusually demanding application in mind. Below, I describe both a laptop and desktop systems for each of two levels of performance. Note that a fast laptop's performance is similar to a basic desktop machine.

Buy the basic level for a good value, especially if your use is mainly word processing and Internet. These specifications are for models which are already discontinued. This means they are selling for an excellent price, but they will be obsolete 6-12 months earlier than the current models. Still, these machines are capable of running all of today's most sophisticated multi-media software. Expect to replace this machine in 2-4 years.

Buy the fast machine if you are interested in processing multi-media graphics -- for example, on-line video editing or for the best performance in the latest computer simulation games. This machine will do pretty much anything you want for 6-12 months longer than the basic machine specified above.

Expect to pay the amount shown. The more you shop around, the less you'll pay. Estimated street prices are as of October, 2000. In 6-12 months, the fast machine specified below will sell for what the basic machine does today, and so on.

Desktop System

You should also make sure the system includes CD-Player, audio and speakers, 56 Kbps fax modem, Windows ME or Windows 2000, and Microsoft Works or equivalent basic productivity software, 1-year parts and labor warranty, 90-day manufacturer's technical support. Not included: network adapter, nor any of the options listed below.

Laptop

You should also make sure the laptop includes CD-Player, audio, 56 Kbps fax modem, Windows ME or Windows 2000, and Microsoft Works or equivalent basic productivity software, and 1-year parts and labor warranty, 90-day manufacturer's technical support. Not included: network adapter, external monitor, keyboard, or mouse, carrying case, any of the options listed below. It would be worth paying extra for the 3-year warranty extension. I would not own a laptop that is not under warranty.

Options:

Inkjet color printer: $150-$300

Microsoft Office Professional Upgrade: $300

Gustavus Community Network Internet access

Review

	A computer is a device that processes information.
	Information is text, pictures, sounds, or anything else that can be encoded in letters and numbers.
	A byte is 8 bits of digital information. Think of it as one letter or number.
	Bytes are grouped into files that are stored in folders on disks.
	Hardware is the metal and plastic that you can see and feel.
	Software is instructions that make a computer do something.
	The operating system is special software that has to be running all the time in order for the computer to do anything.
	There are two main types of  personal computer: PC and Macintosh. The two types have different hardware and software.

Comments and suggestions for training topics and corrections, clarifications, or additions to this document are welcome! You can address them to Nathan Borson, nborson@earthling.net or 697-2313.

View other training information on the Gustavus Public Library web site.