Introduction to Computers: Software

Computer software is anything that can be stored electronically.  The term is used to contrast with computer hardware (the physical objects); unlike hardware, software cannot be touched.  Hardware and software require each other and neither has any value without the other.

Firmware is software that has been permanently stored in hardware.  It is typically not user accessible and usually contains the basic software programming of the device.  Firmware such as the BIOS (Basic Input/Output System) of a personal computer typically contains only elementary basic functions and allows the computer to run more complicated software.

Software refers to the computer programs and data held in the storage of the computer. In other words, software is a set of programs, procedures, algorithms and its documentation concerned with the operation of a data processing system. On most computer platforms, software can be grouped into two broad categories:

System software is the basic software needed for a computer to operate (most notably the Operating System) including:  DOS, Windows, UNIX, Linux, Mac OS, etc.

Application software is all the software that uses the computer system to perform useful work beyond the operation of the computer itself.  Examples of common applications are: word processor, spreadsheet, database, Internet browser, email, games, etc.   Data is all the documents and files that are created or manipulated by application software, including documents, spreadsheets, pictures, movies, etc.

Trav’s Tips:  There are many terms used for the process of accessing software including running, executing, starting up, opening, booting, etc.  All software is stored in files on a storage device. 

System Software:  Operating Systems

All computers need some sort of Operating System (OS) to function. The majority of modern home computers use some form of Microsoft’s operating systems (Apple computers made up only 13.5% of new home computer sales in 2012).

The original Microsoft operating system was called DOS (Disk Operating System) and was replaced by a pretty, mouse controlled Graphical User Interface (GUI) that Microsoft called Windows. Windows comes in various versions beginning with version 3.x then 95, 98, ME, XP, Vista, 7 and 8.  Apple’s Mac computers use their own operating system beginning with Apple OS 1 though to OS X 10.8 and are commonly referred to by cat names including Tiger, Leopard, Snow Leopard, Lion and Mountain Lion.  Linux is a free operating system that has many of the functions of Windows or Apple OS.

The operating system controls the flow of information to and from the CPU.  Basically the computer starts from scratch every time you turn the power on and it first needs to load the operating system (booting up).  It automatically checks all its components and then loads into the operating system.   Once the operating system is loaded the user can start an application or program.  Application software is created to work on specific operating systems only. 

Application Software

There are millions of different pieces of application software available for almost every conceivable need.  The four basic types of applications are:

  1. Commercial software comes prepackaged and is available for purchase from software stores and through the Internet.
  2. Shareware is software developed by individual and small companies that cannot afford to market their software worldwide or by a company that wants to release a demonstration version of their commercial product. You will typically 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.
  3. Open Source software is created by a collaboration of programmers working together. Open source programs are often open for anyone to contribute to and the end products of open source projects are commonly released for public use. 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. There is usually a copyright notice that must remain with the software product and is similar to freeware.
  4. Freeware is created by generous programmers and developers and released is distributed freely, usually accompanied a copyright notice and terms of service that must remain with the software product. Freeware is generally free for anyone to use and distribute so long as the copyright notice and terms of service remain with the software.

Trav’s Tips:  Open source software continues to improve and the quality of open source applications is often equal to, or even better than that of proprietary software.  Currently there are excellent free alternatives to popular (and expensive) traditional popular software suites and programs (LibreOffice or Open Office rather than Microsoft Office, Gimp rather than Adobe Photoshop, Microsoft Security Essentials rather than Norton or McAfee Antivirus, etc.). 

Software Learning Check

  1. T or F              A major difference between hardware and software is that you can touch hardware.
  2. T or F              The computer’s BIOS must run in order for the operating system to function properly.
  3. T or F              Application software is written to work on a specific operating system.
  4. T or F              Computers basically function by accepting input, storing that input and proving output.
  5. T or F              Microsoft Windows is a type of computer BIOS.
  6. T or F              Microsoft Windows 8 and Apple Mountain Lion are basically the same thing.
  7. T or F              You must buy commercial software in order to have a good working and fully featured word processor or spreadsheet program.
  8. T or F              The operating system must be running in order to start a software application.
  9. T or F              You can install Windows system software on a modern Apple Macintosh computer.
  10. T or F              Most hardware peripherals such as printers and DVD drives contain firmware.

Files, Folders and Directories

On the computer’s storage disk, data is stored in files and organized into directories (or a collection of folders).

Trav’s Tips:  Think of a data file as a piece of paper and your computer’s hard drive as a filing cabinet.  You can save the piece of paper in a folder and give that file and folder unique names.  You can save one or many files in this folder and you can save multiple folders (with their own files stored inside) within other folders.  All these folders and the files within them are saved and stored within the filing cabinet (the computer’s hard drive).

Directories can have sub-directories and sub-sub-directories many levels down. The directory immediately below the current directory is called the child directory. The directory immediately above the current one is called the parent directory. The top of the directory structure is called the root directory – creating an (upside down) directory tree.

When a user adds or installs a new program on the computer, the installation process will usually create a new directory or folder to store the application’s files.  When saving a document created by an application, the program will typically try to save to a default directory.

Users can create and delete directories or folders as the need arises.   You can also easily move files from one folder (or directory) to another using menu commands (cut, copy, paste) or by using a mouse to drag and drop. It is important to understand your computer’s directory structure as a file can be misplaced if it is saved in the wrong directory.

Trav’s Tips:  One of the main problems new users have is creating a filing system before it gets too large and difficult to easily find files. Modern operating systems address the ‘filing problem’ by automatically creating a (My) Documents folder. By naming and saving documents in this folder you will always know where to look for your files. Create sub-folders within this folder for your main projects, and use Pictures, Movies, Music, Download, etc. directories as appropriate. Remember to name your files and folders in a logical pattern (that you will remember) and stick to it – search functions are your friend!

As we discussed before, the work that is produced using an application or program is also software (data) and is usually referred to as a file or a document.  Files can be manipulated in a myriad of ways.  They can be opened, closed, edited, saved, printed, backed up, etc.

Saving Files or Documents

In order to save a new document or file you must first choose the Save command. Most modern software applications place this command in a menu. Each file must be given a filename so it can be found easily the next time it is needed.

Many modern software programs (applications) add their own extension to filenames. These extensions allow operating systems to recognize certain filenames and associate (match) them to the program that created it.  Typically they are in a three-letter (sometimes four-letter) format following a period at the end of the file name.

As well as choosing a filename, users must choose a directory and/or disk to store the file in. Remember:  make sure that you are consistent and use a logical structure – the default option is often not the best one for you. 

Common File Types and Extensions

Common file extensions that are good to know, organized by file format.

Text Files

  • .doc         Microsoft Word Document
  • .docx      Microsoft Word Open XML Document
  • .msg        Outlook Mail Message
  • .rtf           Rich Text Format File
  • .txt           Plain Text File
  • .wpd       WordPerfect Document
  • .wps       Microsoft Works Document

Data Files

  • .csv         Comma Separated Values File
  • .dat          Data File
  • .pps         PowerPoint Slide Show
  • .ppt         PowerPoint Presentation
  • .pptx       PowerPoint Open XML Presentation

Audio Files

  • .m3u       Media Playlist File
  • .m4a       MPEG-4 Audio File
  • .mid        MIDI File
  • .mp3       MP3 Audio File
  • .wav       WAVE Audio File
  • .wma      Windows Media Audio File

Video Files

  • .avi          Audio Video Interleave File
  • .flv           Flash Video File
  • .mov       Apple QuickTime Movie
  • .mp4       MPEG-4 Video File
  • .mpg       MPEG Video File
  • .rm          Real Media File
  • .vob        DVD Video Object File
  • .wmv      Windows Media Video File

Image Files

  • .bmp       Bitmap Image File
  • .gif           Graphical Interchange Format File
  • .jpg          JPEG Image
  • .png         Portable Network Graphic
  • .psd         Adobe Photoshop Document
  • .thm         Thumbnail Image File
  • .tif            Tagged Image File
  • .pdf          Portable Document Format File

Database and Spreadsheet Files

  • .db           Database File
  • .xlr           Works Spreadsheet
  • .xls           Excel Spreadsheet
  • .xlsx         Microsoft Excel Open XML Spreadsheet

Executable Files

  • .app         Mac OS X Application
  • .bat          DOS Batch File
  • .com        DOS Command File
  • .exe          Windows Executable File

Miscellaneous Files

  • .bak         Backup File
  • .bin          Binary Disc Image
  • .cfg          Configuration File
  • .cue         Cue Sheet File
  • .dmg        Mac OS X Disk Image
  • .html        Hypertext Markup Language File
  • .ini           Windows Initialization File
  • .ico          Icon File
  • .iso          Disc Image File
  • .java        Java Source Code File
  • .lnk          Windows File Shortcut
  • .pkg         Mac OS X Installer Package
  • .rar          WinRAR Compressed Archive
  • .sys         Windows System File
  • .tmp        Temporary File
  • .torrent     BitTorrent File
  • .7z           7-Zip Compressed File
  • .zip          Zipped File

The Desktop

The Desktop offers many features that make using your computer easier. It is the graphical user interface (GUI) for the operating system that allows the user to interact with the computer in a visual manner using a mouse.  All modern consumer operating systems use a visual desktop to easily access programs or applications.

All programs, folders, tasks and most other operations open in a window on top of the desktop (Macintosh OS is the same as Microsoft Windows in this way).

Desktop Menu

The Windows Start Button menu (or start screen in Windows 8) or the Apple menu has a variety of uses including running programs, opening documents, and accessing most software and features on the computer system.

Common Desktop Menu items:

  • Shortcuts to installed programs.
  • A list of recently accessed documents and programs.
  • Settings to adjust system components, such as printers, control panel and taskbar.
  • Find/Search to find files, folders and phrases in documents on your computer.
  • Help to display an instruction manual and topics broken up into contents and index components.
  • Shut down options to power down, restart or put the computer to sleep.

Windows Explorer and Apple Finder

These applications are basic tools designed to display the components of the computer including disk drives and networks and the software saved on the drives.  All parts of the computer can be accessed through the displayed hierarchical structure.  Select an icon to view the contents of a disk, folder or to run a program.

When an operating system is first installed on a Windows computer, it assigns letter names alphabetically to the storage drives in the format ‘C:’.   Historically ‘A:’ and ‘B:’ were reserved for floppy disc drives and as such are no longer used.  So when viewing your computer, you will likely see the following:

C:                     The computer’s main hard drive where the operating system and programs are installed.  This drive will also very likely have a name (such as ‘computer hard drive’).

D:                    The computer’s optical (CD, DVD, or Blu-ray) drive (if installed).

E:, F:, etc.        The following letter names may refer to any type of storage drive currently connected to the computer (hard, removable, optical, USB, etc).

When you select the drive (in Explorer or Finder) you can then start to navigate and interact with the folder and directory structure where programs and files are stored.

Trav’s Tips:  To select multiple files or folders sequentially in a list, click on the first file (left mouse button) and move to the last file. Hold down the Shift key and select the last file in the sequence.  To select files one at a time (non-sequentially) click on the first file and hold the Ctrl key while selecting the rest.  These two methods can be used in combination. 

Files, Folders and Directories Learning Check

  1. T or F              The root directory is exactly what the name implies: the most basic level in the directory tree.
  2. T or F              A lower-level directory is called a subdirectory.
  3. T or F              The top-most level of the directory tree is called the root.
  4. T or F              Folders and directories refer to different things.
  5. T or F              Software applications are associated with specific extensions.
  6. T or F              You can determine what a document does by its extension.
  7. T or F              You can edit a file called happy.mp3 in a word processor.
  8. T or F              The Windows operating system is usually installed on the B: drive.
  9. T or F              Both Apple OS and Windows use a desktop that is an example of a GUI.
  10. T or F              It is always the best practice to accept the default directory and name when saving a file.


Menus are the most common way of interacting with or controlling your software. Though each program has its own menu, modern software developers typically use standardization in how they create the menus. Many programs have a menu called “File” which controls things like Opening, Saving and Printing your file and Exiting the program. The “Edit” menu contains the main editing commands like Cut, Copy and Paste.  The “View” menu contains zoom and toolbars.  The “Help” menu contains an interactive manual for the program.  Other menu options will appear depending on the function of the software.

The items on the menu are Commands or the features of the program. You choose the command that you want with the keyboard, mouse, trackball or touchpad. Commands control the operation of the software.

Menu bars are usually positioned at the top of the screen and are accessed by moving the cursor to the menu and pressing the left mouse button. This displays a pull-down (drop-down) menu with a number of commands or features.

Trav’s Tips:  Menus and commands can be controlled through the keyboard as well as the mouse. This is an advanced tip and is a great way to speed up tasks.  The most common way of accessing Windows menus through the keyboard is by pressing the Alt key and using the Arrow or Cursor Movement keys to move through the menu items, then pressing Enter to choose the item you want. Many menu items can also be accessed using Hot Key combinations – typically displayed in bold or beside the command name.

Menus are created in a hierarchy. Some menu items branch out to give even more choices. Some menu items open Dialog Boxes that allow you to choose from a number of different options.

Dialog boxes allow computer users to select different options. Some dialog boxes have multiple Tabs (appearing like file folder tabs along the top of the box), which can be clicked to choose more options. These options are then Applied or Saved.  Choose Cancel to close the dialog box without applying the changes selected. Note that options set with the Apply button cannot be canceled this way.


Most software places the most popular commands on a Toolbar for easier access. Simply select the menu item to access a particular command. These tool bars can usually be customized (in the View menu) and often allow the user to move, customize or hide items/buttons and toolbars. 

Context Menus

Windows and Apple OS have a context sensitive menu that is activated with the right mouse button. When the right mouse button is clicked over an object on the screen or area of the screen, a specific menu with commands related to that object will be displayed. The context menu is unique and changes depending on what is selected. This is usually a quick way to select menu items, or to do common tasks such as copy and paste with the mouse.

Right click on:

  • An empty space of the desktop to change Desktop Properties.
  • A file or directory to copy, paste, move, delete, duplicate, get more information, etc.

Trav’s Tips:  This type of menu structure, dialog boxes and toolbars is quite consistent regardless of the type of program (word processing, web browser, email, etc.) and is used in applications for most modern operating systems (Windows, OS, or Linux).  So once you are comfortable with navigating a specific program (such as Word for Windows) you may be surprised how transferrable your skills are to a different Windows program, or even applications for Mac or Linux (and vice versa). 

 Compression and Decompression

Most software you buy download is compressed. Computers store information in bytes, which are made up of on and off signals. The software applications that use these files need to have all the on and off signals (bytes) in place.  However, when the file is stored or downloaded, it can be modified to take up less space on the storage disk.

There are many commercial and free programs that will compress and decompress files for you. The most popular forms of data compression are zip or rar but there are others as well.

Installing New Software

Most software sold today has an automated install sequence that is activated with the press of a button. The installation process will create a directory to store the files related to the new program, decompress and copy the files to the directory and often add a link to the program to the desktop. Many installation processes will also copy files to other parts of the computer and register itself with the operating system by updating the registry. The Windows registry is a database that stores configuration settings and options on Microsoft Windows operating systems.  Some programs will also associate themselves to a certain filename extension.

Trav’s Tips:  Be vigilant when going through the installation steps.  Often software companies make deals with other companies to include their software as well in the installation.  Installing this software is enabled by default and must be de-selected.  Otherwise you may be installing more than you wanted.

Removing software can also be an automatic process. Uninstalling programs will not always remove everything that was installed. Data files that were created with the program will not be removed. Also some fonts and clipart may be left behind. Some programs do not remove their registry settings.


The promise of a paperless office has not happened, though conservation is catching on and it is possible to reduce paper consumption by using your computer more effectively. Having said that, many computers are attached to printers and there are lots of excellent reasons to print out documents that you create on your computer. Most software programs and applications allow the user to print the information that is created in the program.  A printer can be attached directly to your computer using a cable or connected through a network.

Trav’s Tips:  When choosing a printer, consider the cost of additional equipment that you will need as well as the actual printer. Peripherals include paper, ink cartridges, toner etc.  Laser printers use toner rather than ink cartridges and can be more economical in the long run for a lot of printing. 

Word Processing

A word processor is a program used to type documents. Documents can be saved, printed, closed and the opened again to continue working on them.

There are many word processing programs including Open Office Writer, Microsoft Word, Corel WordPerfect and others. Windows comes with WordPad to edit and format documents and NotePad to edit text. Mac OS X comes with TextEdit or SimpleText in previous version. Open Office is an Open Source office application that can be downloaded for free at

Editing functions such as inserting, deleting, editing, moving, and copying characters, words, lines, and even blocks of text are fast and easy. Advanced programs will number pages, repeat material in the same place on every page automatically, and check the spelling of every word in your document. You print your document only after it looks exactly the way you want it to. In computing, WYSIWYG is an acronym for “what you see is what you get”.

A font is the shape and size of a character of text. The three main types are serif (with tails); sans-serif (without tails); and script (similar to handwriting). Text colors can also be changed.


Spreadsheets are used to work with numerical and financial information. Spreadsheet charts are laid out in numbered rows and lettered columns. Where the row and column intersect is called a cell. The letter and number of the intersection refer to the ‘address’ of the cell. The first cell in a chart is at the intersection of column A and row 1 and is referred to as Cell A1.

Some commercial Spreadsheets are Microsoft Excel , Corel QuatroPro , Lotus 123 and others. Calc is an Open Source office program that is free to download and use. Tax and accounting software often use spreadsheets that are designed to provide job specific tools and utilities.

Spreadsheets use formulas to create mathematical equations, from simple to complex. A sheet can be built to handle the financial needs of businesses, or may be used to simply create a list of text.  Most spreadsheet programs include templates to handle many of the average financial needs of a home user or small business. These templates can be modified or customized to personalize them for your own needs.

Most of the standard editing features are available in the spreadsheet such as Bold, Italics, Underline, Move, Copy and Paste.  Information from a spreadsheet can also be displayed in chart form – which is handy for presentations.  Most modern spreadsheet programs allow users to work on many sheets at once and access information from any of the sheets in the workbook group.

Trav’s Tips:  Depending in your system’s resources you can have many programs running at the same time and easily switch from one to another using a couple methods:  while holding down the Alt key (Windows) or Apple key (Mac), tap the Tab key to cycle through a menu of running tasks or click on the taskbar or dock icon of the task you want to bring it to the front.


Graphics Software

There are basically two types of computer graphics:

  1. Bitmapped graphics are images that are mapped to the monitor or screen. The screen is made up of tiny dots called pixels. These dots can display various colors using shades of red, green and blue (RGB).
  2. Vector graphics use objects created from mathematical formulas to represent things like lines, curves, fills, line thickness, etc. to create the image.  Vector graphics can usually be scaled (enlarged or reduced without losing definition.

Graphics formats are distinguished by their filename extensions.  The three main bitmapped format graphics used on the Internet are .gif, .jpeg (.jpg) and .png, however there are many others including: .bmp, .tiff (.tif), .pcx, .ppm, .tga, etc.

Bitmapped graphics can be created and modified in a paint program and vector or structured graphics can be created and modified in a draw program.  Commercial graphics programs include: Photoshop, GIMP,, Illustrator, Maya, etc. 

Sound Software

To listen to sounds on your computer it must have a sound card and audio software installed.

The Moving Picture Experts Group (MPEG), commonly called MP3 is a multimedia format that is an attempt to create standardization among sound formats. MP3 has become extremely popular as a way of downloading, storing and playing music files in a compressed format. MP3 is a patented encoding format for digital audio, which uses a form of lossy data compression; lossy compression is a data encoding method that compresses data by discarding – losing – some of it. It is a common audio format for consumer audio storage, as well as the standard for music on most digital audio players.

Trav’s TipsFLAC (Free Lossless Audio Codec) is a codec (compressor-decompressor or coder-decoder), which allows digital audio to be losslessly compressed such that file size is reduced without any information being lost. Digital audio compressed by FLAC’s algorithm can typically be reduced to 50–60% of its original size, and decompressed into an identical copy of the original audio data.  Note:  Apple iPod and iTunes do not support FLAC format files. 

Video Software

There are many different types of video files and the software required to play them.  You may have seen .gif animations on the Internet. A GIF animation is a series of separate images or frames that display one after the other to give the impression of movement. Other video formats are Audio Visual Interleave’s .avi, the before mentioned mpeg, Microsoft’s Media Player .wmv, Apple’s Quick Time .qt, .aif and .mov, RealNetwork’s RealVideo .rm, Adobe’s Flash which creates Shockwave .swf,.  There are many more examples. 

Software Learning Check 

  1. T or F              Commands for a program are usually located in a drop down menu found in the menu bar.
  2. T or F              Some menu items will spawn (pop-up) a dialog box.
  3. T or F              You can usually change the View options to select what toolbars (and items on the toolbars) that you want to see.
  4. T or F              Context menus are only used in Windows applications.
  5. T or F              It takes longer to download a compressed file.
  6. T or F              MP3’s are perfect compressed copies of the original music file.
  7. T or F              Most word processors use a WYSIWYG design.
  8. T or F              You can only store numbers in a spreadsheet.
  9. T or F              A bitmap file is a video file.
  10. T or F              Installing new software on a Windows computer updates the registry.