Computer Software

Learning Objectives

• Distinguish between software and hardware.
• Describe system software and application software.
• Explain utility software, firmware and drivers.
• Describe the main types of software licence.

Software vs Hardware

Computer software is a collection of instructions, data, and programs that tell the hardware what to do. Hardware is the physical body of the computer; software is the mind that gives it purpose. Without software, hardware sits idle, and without hardware, software has nothing to run on.

Hardware is physical and can be touched. It wears out over time. It cannot be changed by the user easily. Examples include the CPU, keyboard, and monitor. Software is virtual and consists of instructions. It does not wear out but can become outdated. It can be installed, updated, and removed. Examples include Windows, Chrome, and MS Word.

Software is broadly classified into three main categories, namely system software, application software, and utility software.

System software is the most fundamental layer. It manages the computer's resources, provides a user interface, and allows application software to run. The most important system software is the operating system (OS). Application software is designed to help users perform specific tasks, such as word processors for creating documents, spreadsheets for handling numbers, web browsers for accessing the internet, and presentation software for creating slide shows.

Utility Software, Firmware, and Drivers

Utility software helps maintain, configure, optimise, or protect the computer. Common utilities include antivirus programs that detect and remove malware, disk cleanup tools that free up storage space, file compression tools that reduce file sizes for storage or transfer, backup utilities that create copies of important files, and disk defragmenters that reorganise data on a hard drive for faster access.

Firmware is a special type of software permanently stored inside a hardware device. It tells the device how to function at a basic level. Examples include the BIOS (Basic Input/Output System) in a computer motherboard, which controls the startup process, and the firmware in a printer that manages printing functions. Firmware can sometimes be updated to fix bugs or add new features.

A device driver is software that allows the operating system to communicate with a specific hardware device. Without the correct driver, the OS does not know how to control the device. For example, without a printer driver, the computer cannot send print jobs to the printer. Without a graphics card driver, the screen may display low resolution or lag.

Software Licensing

A software licence is a legal agreement between the software creator and the user. It defines how the software may be used, copied, and distributed. Different licences offer different rights.

Licensing protects both the creator and the user. Creators receive payment or recognition for their work. Users are protected by knowing what they are allowed to do with the software. Using proprietary software without paying for it (piracy) is illegal and unethical. Open-source software offers transparency because anyone can inspect the code for security or quality. In Nigeria, many schools use open-source software such as Linux and LibreOffice because it is free and reduces costs.

System Software Categories versus Application Software

System software is the set of programs that runs and manages the computer itself, while application software is the set of programs that users operate to perform specific tasks. This division helps users understand why a computer needs two very different kinds of software working together at the same time.

System software is divided into three main categories. The operating system (OS) controls the processor, memory, storage and input/output devices, and provides the interface users see. Utility software maintains and protects the system, such as antivirus programs and disk cleaners. Device drivers are the third category; each driver is a small program that lets the operating system speak with a specific piece of hardware such as a printer or a scanner.

Application software serves the user directly. Word processors such as Microsoft Word, spreadsheets such as Excel and browsers such as Chrome are all applications. A Nigerian bank clerk uses a banking application to record transactions, but every application depends on the operating system underneath to run.

The operating system manages hardware and provides the user interface.

Utility software maintains, optimises and protects the computer.

Device drivers connect the OS to individual hardware components.

Application software helps users carry out specific tasks such as typing, calculating or browsing.

Software Acquisition and Licence Types

Software reaches users through several channels. It can be bought as a boxed product, downloaded from the internet, bundled with new hardware or obtained as open-source code. Each method affects the licence under which the software is used.

Proprietary software is owned by a company that controls its use and distribution. Microsoft Windows and Adobe Photoshop are examples. Shareware is proprietary software distributed free for a trial period, after which the user is expected to pay. Freeware is proprietary software that is free to use but still closed, meaning the source code is not shared.

Open-source software publishes its source code so anyone can view, modify and distribute it. Linux, LibreOffice and Firefox are examples. In Nigeria, many schools save money by installing Linux and LibreOffice on their computer labs instead of purchasing proprietary equivalents.

Purchase and download are the two main ways to acquire commercial software.

Shareware allows free trial use before a mandatory payment or registration.

Freeware is free to use but the source code stays hidden.

Open-source software shares its code and is often free for schools to adopt.

How Software Controls Hardware

Software controls hardware through a chain of instructions that begins at the operating system and ends at the physical component. When a user presses a key, the key press reaches the CPU through the device driver, then the operating system decides which running application should receive it, and the application responds on the screen.

The operating system plays the central role in this chain. It allocates CPU time, reserves memory for each program, manages files on the disk and schedules when data is written to storage. Without the OS, applications would have no way to reach the hardware.

The interrupt system shows the OS at work. When hardware such as the mouse needs attention, it sends an interrupt signal to the CPU. The CPU pauses the current task and runs the OS handler for that device, then returns to the previous work. This is how a computer can type a document, play music and show a video at the same time.

Device drivers translate OS commands into signals that hardware understands.

The OS schedules tasks so every running program gets a fair share of the CPU.

Interrupts let hardware request CPU attention when data is ready.

Practical Work

1. Group a list of programs into system and application software.
2. Draw a table comparing system and application software.
3. Name three types of software licence and one rule of each.
4. Explain why a driver is needed for a printer.

Scenario-Based Questions

1. A cash-strapped school installs Linux and LibreOffice on all its computers. Identify the category of software each belongs to, and explain why the open-source licence makes this cheaper than Windows and Microsoft Office while still being legal.
2. After a system update, the school printer refuses to print and the operating system says it cannot control the printer. Predict the missing software and explain how a device driver lets the OS and the printer work together.
3. A student installs an antivirus program and a file compression tool on a school machine. Classify each as system, application, or utility software, and state exactly what each one does.
4. A software company wants to sell a product with secret source code, while a poor school needs the cheapest legal office programs. Compare proprietary and open-source software and justify a recommendation for the school.
5. A student downloads a pirated copy of Windows to avoid paying. Using the licensing rules in your note, explain why that is illegal and unethical, and name a legal alternative the school could use for the same class work.
6. An old desktop has no graphics card driver installed, so the display is blurry and slow, and there is also no audio driver. Using the driver table, predict what happens to the display and to the sound, and what the repair shop should install.
7. A school office wants to protect files from loss, free up disk space, and email smaller attachments. Name the three utilities in your note that do each job and explain why each is the right tool.

Lesson objectives

By the end of the week, learners should be able to:

1. Restate system software and application software definitions.
2. Name five functions of an operating system.
3. Distinguish firmware from regular system software.
4. Explain the role of a utility program such as antivirus software.
5. Classify thirty software items into system, application or both.

Key vocabulary

• Software: the programs that tell hardware what to do.
• System software: programs running and managing the computer.
• Application software: programs solving a user task.
• Operating system: manages hardware, files, memory and programmes.
• Firmware: permanent instructions on a chip such as boot loader.
• Utility program: a maintenance tool such as antivirus or disk cleanup.
• Boot loader: programme loaded at start-up to begin the OS.
• Driver: system software letting hardware talk to the OS.

Common misconceptions

• "Windows is an application." Windows is system software; Microsoft Word is the application.
• "Software is something you can hold." A CD contains hardware; the program on it is software.
• "Firmware disappears after a reboot." Firmware persists across reboots as permanent instructions.

Teacher activities

1. Starter: hold up a keyboard and a screenshot of an installer; ask which is hardware and which is software.
2. Restate the system versus application definitions and add five OS functions.
3. Introduce firmware as permanently stored on a chip and distinguish it from utilities.
4. Model naming a driver and a utility program with examples.
5. Set the thirty-item software classification task and require reasons for four items.
6. Close with the exit question distinguishing firmware from application software.

Student activities

1. State the system versus application definitions and give two examples each.
2. Name five operating-system functions in one to two lines each.
3. Distinguish firmware from a utility program with one example each.
4. Classify a driver and a utility program correctly with examples.
5. Complete the thirty-item software classification with reasons.
6. Answer the exit question in one sentence about firmware.

Practical / learning evidence

A fifteen-software classification table with columns Software, System, Application, Example and Reason. Plus a ten-item firmware-versus-utility chart. Hand in both for marking.

Resources and preparation

Keyboard, mouse and a screenshot of installed applications. Blank classification tables and item cards. Offline route: printed cards and tables. Do not let learners install or uninstall anything on laboratory machines.

Assessment for learning

Mark the classification for accuracy and reasons. Check the firmware chart for one correct example of firmware and one of utility. Watch for "Windows is an application" and correct it live.

Inclusion and homework

Provide the item cards in larger print and allow oral completion. Extend confident learners with thirty items and a second firmware example. Homework: list three application programs on any device and state the task each performs.