Information Technology Center

Computer Software

This lecture focuses on:

1. System Software
2. Application Software
3. Closed source
4. Open source

What Software is

Software is a set of instructions that tell a computer exactly what to do. All computer programs are software. Naturally, these include very powerful programs like Microsoft Windows 10 and 11, wordprocessing applications like Microsoft Word and spreadsheet applications like excel and google sheets to name a few. Software comes in two main categories :

1. System Software
2. Application Software

System Software

System software controls a computer's internal functioning. The system software is the interface between the hardware and user applications. It is designed to run a computer's hardware and applications and manage all resources, such as its memory, processors, and devices. There are five major categories of system software :

1. Operating System
2. Utility programs
3. Device drivers
4. Firmware
5. Language translators

Operating Systems are the most sophisticated type of software as they manage all the hardware including the computer memory. The most common operating systems on personal computers are Windows 10 and 11, MacOS and Linux. On smart phones, the most common operating systems are android and iOS. Utilities like backup programs, disk repair programs, and antiviruses are system software.

Application software

Application software are end-user computer programs designed to carry out a specific task. There are many different types of application software available. One important factor to consider before choosing software is ease of use. We use programs more when they are user friendly. No one wants to spend hours learning a complicated program. Users want mouse support and menus that are arranged in an intuitive way (related functions grouped together).

In recent years, the shortened term 'app' has become popular to refer to applictions for mobile devices such as smartphones and tablets. Apps have fewer features and are less powerful than applications designed to be run on personal computers.

Some application programs:

1. web browsers
2. media players
3. word processors
4. spreadsheets
5. presentation applications
6. accounting programs
7. graphics programs
8. databases
9. computer games

Types of application software:

1. general-purpose software
2. specialised software
3. customised software
4. custom-written software
5. integrated software packages
6. malware

Closed Source or Open Source

Application software may be closed source or open source.

Closed source software is software that has the source code encrypted. Meaning, users may not copy, modify, or delete parts of the code.

Open source software is software that does the complete opposite. It allows users to copy, modify, or delete parts of the code under their own discretion.

When you purchase a new computer today it would usually come with an operating system and some application software pre-installed. This means the programs are ready to be used immediately after you boot-up. Some applications can be downloaded free from the internet but most you would have to pay for if your operating system is Windows or Mac OS. The list of application programs available today seems endless.

Activity 2.1

1. The most important software on your computer is the Operating System. What is the name and version of the OS on your computer?
2. Make a list of the application programs installed on your computer
3. Which application do you find most useful?
4. Do you enjoy using that program?
5. Do you consider the program to be user friendly?
6. Is there a program on your computer you never used? If so why?
7. What application software is missing that you would like to have installed?
8. Do you consider yourself a gamer?

Now click HERE for more details on what the OS is and does.