GCSE Computer Science WJEC

Hardware and Communication

Hardware

Hardware refers to the physical components of a computer system which you can physically touch.

• Central Processing Unit (CPU): Known as the 'brain of the computer.' This is where most calculations take place.

• Random-access Memory (RAM): This is the computer's "working memory". RAM temporarily stores data that is being used or processed by the CPU.

• Hard Drive: This is where data is stored on a long-term basis. Even when the computer is switched off, data remains on the hard drive.

• Motherboard: This is the main circuit board of a computer. All other hardware components connect to the motherboard.

• Input/Output Devices: Input devices like the keyboard and mouse allow users to interact with the machine. Output devices like monitors and printers enable the computer to communicate information to the user.

Communication

Communication refers to the processes by which computers exchange information.

• Networks: Computers can be connected together to form a local area network (LAN) or wide area network (WAN). Networks allow computers to share resources and communicate with each other.

• Internet: The Internet is a global network of networks. It connects computers all over the world and provides services like the World Wide Web and email.

• Protocols: These are standardised ways of sending and receiving data over networks. They ensure that data is transmitted accurately and in a way that can be understood by the receiving computer. Examples include HTTP, TCP/IP, and SMTP.

• Wireless communication: Data can be sent wirelessly using technologies like Wi-Fi (used for local area networks) and 3G/4G/5G (used for wider connectivity, as in mobile phone networks).

• Routers and Switches: These are devices that help direct data along the correct path in a network. Routers are typically used in home networks to connect multiple devices to the Internet, whilst switches are commonly found in business and data centres to connect large numbers of machines.

Security

Maintaining security of hardware and communication is paramount.

• Firewalls: These are hardware or software systems used to prevent unauthorised access to a network.

• Encryption: This is the process of converting data into a secure format to prevent unauthorised access. Data must be decrypted before it can be read.

• Virus protection software: This software helps protect against malicious software (malware) such as viruses, worms, and trojans.

• Updates: Regular software and hardware updates are important to ensure security features are up to date and can protect against the latest threats.

• Data backup: Regularly backing up data ensures it can be restored if lost due to hardware failure, accidental deletion, or a security breach.