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Software
The software is the information that the computer uses to get the job done. Software needs to be accessed before it can be used. There are many terms used for process of accessing software such as running, executing, starting up, opening, and others.
Computer programs allow users to complete tasks. A program can also be referred to as an application and the two words are used interchangeably.
Examples of software programs or applications would be the Operating System (DOS, Windows 9x/Millenium, O/S2, UNIX, MacOS and various others), Wordprocessor (typing letters), Spreadsheet (financial info), Database (inventory control and address book), Graphics program, Internet Browser, Email and many others.
As well any document
that you create, graphic you design, sound you compose, file you make,
letter you write, email your send or anything that you create on your
computer is referred to as software. All software is stored in files.
Software is stored on a disk or tape whether that disk is a floppy (or "Zip"), hard disk, CD, tape or one of the dozens of other storage devices available.
There are millions of different pieces of software available for almost every conceivable need. Software is available commercially through stores and mail order and also available on the Internet. If you can't find the application that you need software development companies can custom design software for you.
The largest software companies offer packages of software or suites that include many of the programs that the average person or business needs. Software packages or suites contain programs that work together and share information, making it easier to combine that information in versatile ways. For example when writing a letter you can get the address from a database, include a letterhead from a paint program and included a financial chart in the body of the letter.
The three basic types of software, commercial, shareware and public domain software.
Commercial software comes prepackaged and is available from software stores and through the Internet.
Shareware is software developed by individual and small companies that cannot afford to market their software world wide or by a company that wants to release a demonstration version of their commercial product. You will have an evaluation period in which you can decide whether to purchase the product or not. Shareware software often is disabled in some way and has a notice attached to explain the legal requirements for using the product.
Public Domain software or freeware is created by generous programmers and released into the public domain for public use. There is usually a copyright notice that must remain with the software product. Similar to this is Open Source software. Open Source software is not public domain in that the company or individual that develops the software retains ownership of the program but the software can be used freely. Many popular Open Source applications are being developed and upgraded regularly by individuals and companies that believe in the Open Source concept.
Operating Systems
All computers need some sort of Operating System. The majority of modern home computers use some form of Microsoft's operating systems such as DOS (Disk Operating System) or Windows (3.x, 95, 98, ME or Windows 2000) though some use IBM's O/S2. Macs use their own operating system. In the past large companies and institutions would have an operating system design exclusively for them but as the commercial operating systems become more sophisticated the benefits of this practice is becoming less apparent. Computer professionals, Internet Service Providers (ISP) and mainframe computer users use an operating system such as UNIX (or a variant such as Linux), Windows NT or 2000 (Win2k).
There are many smaller operating systems out there. The problem is that software is currently being developed only for the main operating systems. Many older computers with unique operating systems have lots of software already developed for them but there is very little new software being developed for the older computers. The proprietary operating systems are less likely to offer technical support than the more modern operating systems.
The operating system controls the input and output or directs the flow of information to and from the CPU. Much of this is done automatically by the system but it is possible to modify and control your system if you need to.
When you turn your computer on it first needs to load the operating system sometimes referred to a booting up. Basically the computer starts from scratch every time you turn the power on.
It checks all its components and will usually display a message if there is a problem. Loading the system is usually automatic.
Once the system is loaded the user can start the application or program that they are going to use.
Many users will run Microsoft Windows as their operating system. Windows is a Graphic User Interface (GUI) which allows the user to control or run the computer using a Mouse and Icons. The user simply moves the mouse on a flat surface, rolls the trackball, or moves their hand over the touchpad to control a pointer. They then choose the option they want by pressing a button or touching the pad.
Without Windows the user controls the computer using the keys on the keyboard.
Disk and Storage
Disks are used to store information. All information on computers are stored in files. The size of a file is measured in bytes.
A byte is approximately one character (letter 'a', number '1', symbol '?' etc....).
- About a thousand bytes is a kilobyte (KB).
- About a million bytes is a megabyte (MB).
- About a billion bytes is a gigabyte (GB).
A byte is made up of 8 bits. A bit is simply an on or an off signal which passes through the computers circuitry. Every piece of software can be broken down into a series of on or off signals or it's Binary Code.
* Editor's Note: I say 'about' because everything in computers must be divisible by 8 so a kilobyte is actually 1,024 bytes. The reason for this goes beyond the scoop of an introductory level document but as it can cause some confusion I thought it should be mentioned.
Floppy (or "Zip") disks are still a common way of transporting information (such as bringing files home from work) compact disks (CDs) have become the most popular way of selling software. Hard disks are the most common storage device.
Compact disks or CDs can store large amounts of information. One disk will store 650 Mb or about 70 or 80 minutes of music. They are sometimes referred to as a CD-ROM which stand for Compact Disk Read Only Memory. Some CD drives can copy information or burn information on to a blank CD and others can copy and remove information. Common Read Only CD blanks can only be written to once though more expensive Read/Write CD's can be used over and over again. DVD disks can store over 4 gigabytes but DVD recorders are still quite expensive for the average person.
Hard disks store the majority of information on today's modern computer. My first hard disk stored 52 Mb, 12 more than my colleague's 40 Mb. Today the standard hard disk stores 30 GB or more (this number is always changing). Like a floppy disk information can be stored and deleted as necessary.
Floppy disk or diskette comes in two basic sizes; 5.25 inch (almost obsolete) and 3.5 inch. Both have a low and high density versions though 3.5 inch high density disks are the most common.
 |
Disk size | Amount of storage | Approximate
printed 8.5 x 11 inch pages |
|---|---|---|---|
| 3.5" Floppy | 1.44 Mb | 720 pages | |
| Zip 100 | 100 MB | 50,000 pages | |
| CD | 650 MB | a small library | |
| DVD | 4.5 GB | a feature length movie |
There are many other storage devices including tape, Panasonic's LS120 3.5 inch diskettes, Zip & Jazz disks, VCR tape and many others. Innovation in storage technology is currently advancing rapidly.
Information is stored in an electromagnetic form much like a cassette or video tape.
Note: Keep disks away from strong electric or magnetic fields including x-rays. Be aware of high electromagnetic areas in the room such as televisions, speakers, high tension wires, etc... Use disks only at room temperature and keep them out of direct sunlight. If possible avoid passing electromagnetic storage devices through airport x-rays. In theory information stored on a disk will last indefinitely but the physical storage device will wear out with usage and time.
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