What is ICT? Information technology systems and their stages
ICT stands for information and communication technology. It means the devices, programs and networks we use to collect, process, store and share information. Information technology (IT) is about handling information. Communication is about sending it.
An information system works in stages:
- Input: data goes in (typing, camera, sensor, microphone).
- Process: the computer sorts, counts, edits or decides.
- Output: the result is shown (screen, speaker, printer).
- Storage: the data is kept (disk, memory card, cloud).
- Communication: the data is sent to others over a network.
Example: a weather app. Sensors give temperature (input); the computer finds the average (process); your phone shows a number (output); old values are saved (store).
Communication media: types
A medium is the path a message uses. There are three families.
- Wired (guided) media: twisted copper cable, coaxial cable, and optical fibre (light pulses in thin glass, very fast and far).
- Wireless (unguided) media: radio waves (mobile, Wi-Fi, FM), microwaves, infrared (remote controls).
- Satellite: a signal goes up to a satellite and back, good for ships, planes and remote places.
Do not mix this with mass media (newspaper, radio, TV, websites), which are channels that reach many people. Cable, wireless and satellite are the carriers of the signal.
| Medium | Good for | Weak point |
|---|---|---|
| Optical fibre | Very high speed, long distance | Costly to lay |
| Radio / Wi-Fi | Moving devices, no wires | Signal weakens with distance and walls |
| Satellite | Remote places | Small delay, weather can disturb |
How ICT developed: features of each step
- Telegraph (1830s-40s): coded signals over wire.
- Telephone (1876): voice over wire.
- Radio (early 1900s) and TV (1920s-50s): broadcast to many people.
- Computers (1940s onward): fast processing; later small and personal.
- Internet (1969 first network; the Web in 1989-91): computers everywhere linked.
- Mobile and smartphones (1990s-2000s): a computer in every pocket.
- 5G, IoT and AI (2020s): faster, always-connected things that can decide.
Features of the trend: devices become smaller, faster, cheaper; networks reach more people; separate tools converge into one phone.
Advanced ICT: 5G, IoT and AI
5G is the fifth generation of mobile networks. Compared with 4G it can be much faster, can react with very small delay, and can connect very many devices in the same area. These are best-case features; real speed depends on place and network.
IoT (Internet of Things) means everyday objects with sensors and a network link: a smart bulb, a fitness watch, a farm soil sensor, a car. They send data and sometimes receive commands.
AI (artificial intelligence) lets computers find patterns and make decisions, such as a camera that spots a defect in a factory. Automation means machines doing a task with little human help. ICT and AI engineers design the networks, chips, software and robots; automation engineers link sensors, controllers and machines.
A hyper-connected society: benefits and risks
In a hyper-connected society people, machines and places are linked all the time. Benefits: online classes, telemedicine, smart farming, faster help in disasters. Risks: loss of privacy, hacking, false news, screen addiction, and the digital divide (people without devices or internet fall behind). Sustainable ICT also thinks about energy use of data centres and about e-waste (old phones and computers). Use strong passwords, update software and share carefully.
Try it
In the 3D, switch devices on and off at the last step and watch the counter. At home: list five things in your house that take input and give output. Then draw the path of one WhatsApp-style message from your phone to a friend: which media does it use?
Key formulas and definitions
- ICT = Information + Communication + Technology
- Information system: Input β Process β Output β Storage (β Communication)
- Media: wired (copper, fibre), wireless (radio, microwave), satellite
- Transfer time = file size (in bits) Γ· speed (in bits per second)
- 1 byte = 8 bits
Worked examples
1. Name the four stages of an information system for a digital camera.
Input: light through the lens and sensor. Process: the chip makes the picture. Output: the picture on the screen. Storage: saved on a memory card.
2. Which medium would you choose for a ship in the middle of the ocean, and why?
Satellite. There are no cables or towers there, and a satellite signal can reach the ship from space.
3. A 50 MB video is sent at 10 megabytes per second. How long does it take?
Time = 50 Γ· 10 = 5 seconds. If the speed is given in megabits per second, first multiply the file size by 8 (50 MB = 400 Mb).
Common mistakes
- Mixing up the medium (cable, radio, satellite) with mass media (TV, newspaper). The medium carries the signal; mass media are channels for many people.
- Forgetting storage as a stage of an information system.
- Mixing bytes and bits: network speeds are usually in bits per second (Mbps), file sizes in bytes (MB). 1 byte = 8 bits.
- Thinking 5G is only "faster phones". It also means low delay and many connected devices (IoT).