Everything we see and touch inside and around a computer can be divided into two broad families: hardware and software. Hardware means the physical, tangible parts of the computer that we can see and touch, such as the keyboard, monitor, mouse, printer and the wires inside the system unit. Software means the set of instructions, called programs, which tell the hardware what to do. Hardware alone cannot work; it needs software to give it commands, and software alone cannot work; it needs hardware to execute its commands. Both are equally important, and together they make the computer useful.
Hardware is classified into four types according to the job it performs. Input hardware is used to feed data into the computer, such as the keyboard and mouse. Output hardware displays or prints the results, such as the monitor and printer. Storage hardware saves data permanently, such as the hard disk, pen drive and optical disc. Processing hardware is the internal circuitry that does the actual work, most importantly the motherboard and the microprocessor. The motherboard is the main circuit board that connects all the internal components together, and the microprocessor is the chip that holds the CPU.
Software is a collection of programs. A program is a sequence of instructions written in a programming language that tells the computer exactly what to do. Software can be broadly divided into two categories: system software and application software. System software manages the computer itself and helps the hardware and application software work together. Application software helps the user perform a specific task such as typing a letter, making a budget or playing a game. There is also a third category called utility software, which is actually a part of system software and is used to maintain and repair the computer.
The most important system software is the operating system. It is the first program that loads when the computer is switched on and it stays in memory until the computer is turned off. The operating system performs five main jobs: it manages the memory, manages the files, manages the devices, manages the processor, and provides the user interface through which the user gives commands. Examples of operating systems are Windows, macOS, Linux and Android. Without an operating system, a computer is just a box of wires that can do nothing.
Application software is designed for a particular user task. Word processors such as Microsoft Word are used to create text documents. Spreadsheets such as Microsoft Excel are used to calculate and analyse numbers. Presentation software such as PowerPoint is used to make slide shows. Graphics software such as Paint and Photoshop is used to create and edit pictures. Database software is used to store and organise records. Web browsers such as Chrome and Firefox are used to view pages on the Internet, and media players are used to play music and video.
Utility software helps to keep the computer healthy. Antivirus programs scan the computer and remove viruses. Disk cleanup tools delete unneeded files and free up space. Disk defragmenters rearrange the data on a hard disk so that files open faster. Backup tools copy important data to a safe place. Firmware is a special type of software that is stored permanently inside a hardware device, such as the ROM chip of a computer. Firmware cannot be changed easily by the user and acts as a bridge between the hardware and the software.
Hardware and software depend on each other completely. When a user types on the keyboard, the hardware sends the signal, and the software translates the signal into a letter on the screen. When a game is played, the software sends instructions and the hardware, such as the graphics card and speakers, executes them. This relationship can be compared to a human body: hardware is the body, and software is the mind. If the body is damaged, the mind cannot act; if the mind is absent, the body cannot think. In the same way, both are needed together for the computer to function.
Every software has system requirements, which are the minimum hardware conditions needed to run it, such as processor speed, amount of RAM, hard disk space and display quality. Before installing a program, the user must check whether the computer meets these requirements. Software can be installed from a CD or DVD, from a pen drive, or by downloading from the Internet. During installation, files are copied to the hard disk, shortcuts are created on the desktop, and the program is registered so that it can start whenever the user opens it.
| Type of Hardware | Examples | Purpose |
|---|---|---|
| Input hardware | Keyboard, mouse, scanner | Feed data into the computer |
| Output hardware | Monitor, printer, speaker | Show results to the user |
| Storage hardware | Hard disk, pen drive, DVD | Save data permanently |
| Processing hardware | Motherboard, microprocessor | Perform calculations and control |
| Category | Examples | Main Job |
|---|---|---|
| System software | Windows, macOS, Linux | Manage the computer and its devices |
| Application software | Word, Excel, Paint | Help the user do specific tasks |
| Utility software | Antivirus, disk cleanup | Maintain and protect the computer |
| Firmware | ROM chips, device drivers | Stored inside hardware, permanent |
Hardware and software are the two inseparable partners of a computer. Hardware provides the physical machines that we can touch, while software provides the instructions that make the machines useful. System software manages the computer, application software performs user tasks, and utility software keeps everything healthy. Understanding this relationship prepares us for the next topic — the number systems that the computer uses internally to store and process all this data.