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Understanding ICT: Hardware, Software and Devices
Smart TVs, interactive panels, tablets and DIKSHA on a phone are now part of many Andhra Pradesh classrooms. To use them well, a teacher needs a clear grasp of the basics. The APTET syllabus begins with understanding ICT, computer hardware, software, and input and output devices. Questions in this area are short and factual, so this lesson focuses on clear definitions and comparison tables.
What is ICT?
ICT (Information and Communication Technology) means all technologies used to create, store, process, share and communicate information: computers, mobile phones, the internet, radio, television, projectors, interactive boards and software.
In education, ICT helps to:
- present ideas through pictures, sound, animation and video;
- give access to vast resources (e-books, videos, simulations);
- allow practice at the child’s own pace with instant feedback;
- support children with disabilities through assistive technology;
- connect teachers for professional development.
ICT supports good teaching; it does not replace the teacher.
Computer hardware and devices
Hardware is the physical parts of a computer that you can touch. A computer works in four steps: input, processing, storage and output.
| Part | Function | Examples |
|---|---|---|
| Input devices | send data and commands into the computer | keyboard, mouse, scanner, microphone, webcam, joystick, barcode reader, OMR (optical mark reader) |
| Processing unit (CPU) | the “brain”; carries out instructions | ALU (Arithmetic Logic Unit) does calculations and comparisons; CU (Control Unit) directs all operations |
| Output devices | show or give results | monitor, printer, speakers, projector, headphones |
| Storage devices | keep data for later use | hard disk (HDD), solid-state drive (SSD), pen drive, memory card, CD/DVD |
| Both input and output | accept input and also show output | touch screen, interactive board, headset with microphone |
Memory
| Memory | Feature |
|---|---|
| RAM (Random Access Memory) | primary, temporary working memory; volatile: data is lost when power is switched off |
| ROM (Read Only Memory) | primary, permanent; non-volatile; stores start-up instructions |
| Secondary storage | permanent, large; hard disk, SSD, pen drive |
| Cache memory | very fast memory between CPU and RAM |
Units of memory
Bit (0 or 1) is the smallest unit. 8 bits = 1 byte; 1024 bytes = 1 kilobyte (KB); 1024 KB = 1 megabyte (MB); 1024 MB = 1 gigabyte (GB); 1024 GB = 1 terabyte (TB).
Software and its types
Software is a set of programs (instructions) that tells the hardware what to do. You cannot touch software.
| Type | Purpose | Examples |
|---|---|---|
| System software | runs the computer and manages hardware | operating systems such as Windows, Linux, Android, macOS |
| Application software | helps users do specific tasks | word processor, presentation software, spreadsheet, web browser, educational apps |
| Utility software | maintains and protects the computer | antivirus, file compression, backup, disk cleanup |
Software by licence
| Category | Meaning | Examples |
|---|---|---|
| Proprietary | owned by a company; source code closed; usually paid | Microsoft Office |
| Open source | source code is freely available to use, study, change and share | Linux, LibreOffice, Moodle, GeoGebra |
| Freeware | free to use, but source code usually not available | many free apps and readers |
| Shareware | free to try for a limited period or with limited features, then paid | trial versions |
Schools prefer open-source and free software where possible because it reduces cost and can be shared and adapted.
Example
Mrs Kavitha uses a laptop (hardware), Linux and LibreOffice Impress (software) and a projector (output device) to show pictures of animals in a Class 3 EVS lesson. Children use a microphone (input device) to record their own animal sounds, which are saved on a pen drive (storage).
Exam focus
- ALU = calculations; CU = control. RAM is volatile; ROM is non-volatile.
- Touch screen and interactive board are both input and output devices.
- Open source = source code available; freeware = free to use but not necessarily open.
Key takeaways
- ICT includes all technologies for handling and communicating information.
- A computer works through input, processing, storage and output.
- The CPU has an ALU and a Control Unit.
- RAM is temporary and volatile; ROM is permanent.
- Software can be system, application or utility software.
- Open-source and free software help schools save money and share resources.
Practice
- Which of the following is an input device?
- (A) monitor
- (B) scanner
- (C) printer
- (D) speaker
- The part of the CPU that performs calculations and comparisons is the:
- (A) Control Unit
- (B) RAM
- (C) ROM
- (D) Arithmetic Logic Unit
- Memory that loses its data when the power is switched off is:
- (A) RAM
- (B) ROM
- (C) hard disk
- (D) pen drive
- 1 byte is equal to:
- (A) 4 bits
- (B) 1024 bits
- (C) 8 bits
- (D) 16 bits
- Windows, Linux and Android are examples of:
- (A) application software
- (B) utility software
- (C) operating systems
- (D) hardware
- A device that works as both an input and an output device is:
- (A) a touch screen
- (B) a keyboard
- (C) a projector
- (D) a mouse
- Software whose source code is freely available to use, study, modify and share is called:
- (A) shareware
- (B) proprietary software
- (C) a virus
- (D) open-source software
- Antivirus software is an example of:
- (A) system hardware
- (B) utility software
- (C) input software
- (D) an output device
Answers and explanations (tap to show)
- (B) A scanner sends images into the computer; the others are output devices.
- (D) The ALU performs arithmetic and logical operations; the Control Unit directs operations.
- (A) RAM is volatile, temporary working memory.
- (C) One byte is 8 bits.
- (C) These are operating systems, a type of system software.
- (A) A touch screen displays output and accepts touch input.
- (D) Open-source software makes its source code freely available.
- (B) Antivirus is utility software that protects the computer.