IGCSE Flashcards
Hardware
The physical components of a computer system
Internal Hardware Devices
Processor Motherboard Random Access Memory Read Only Memory Video and Sound Cards Internal Hard Disk Drive
Processor
Central component of any computer system through which every other component communicates. Components are plugged into it directly or indirectly.
Motherboard
The brain of the computer. It controls everything that the computer does and processes the data, moving it in and out of the memory.
Random Access Memory (RAM)
It stores the information currently in use, which is constantly changing.
A fast, volatile memory since when the computer is turned off the data is lost. The more RAM you have the faster your computer works.
Read Only Memory (ROM)
Used to store instructions for the computer to work. The information cant be changed and when the computer is turned off, it wont be lost. The data can be accessed very fast.
Video Card
Allows images to be displayed on the monitor. Along with its installation, software is installed so it tells the computer how to use it.
Sound Card
Allows the computer to produce and input sounds to and from the computer by turning analogue data into digital and vice versa.
Internal Hard Disk Drive
Stores data that is not instantly needed for an indefinite time. It also stores programmes and is used commonly to back up data.
External Hardware
Inputs
Outputs
Peripherals
Input Devices
Used to get data into the computer system. Manual or automatic.
Output Devices
Used to transfer data out of the computer system. Temporary or permanent.
Peripherals
Non-essential hardware that connect to the computer externally.
Software
Programmes used for controlling the operation of a computer or processing of electronic data.
(Applications S. and System S.)
Applications Software
Software used in particular situations, which can be used either for a general purpose or in one particular situation (specialised).
(Word processing, spreadsheet, data manip…)
System Software
Files and programmes that make up a computer’s operating system.
(Compilers, linkers, device drivers…)
Secondary/Backing Storage
Storage devices and media that are not constantly accessible by a computer system.
Operating System
Software program that manages computer resources. They allow components to communicate with each other and enable the computer to run software applications.
(CLI and GUI)
Command Line Interface (CLI)
The user types in instructions and commands. It is fast but complicated and uses little RAM. It is used in batch processing.
Advantages of CLI
- User communicates directly with the computer.
- There’s a wide range of commands.
- Need very little computer power.
Disadvantages of CLI
- User must remember the complex commands.
- Lots of typing involved.
- High chance of errors.
Graphical User Interface (GUI)
The user points at and clicks objects on a screen with a mouse.
It is easy to use but needs a large amount or RAM and disk space.
It uses Windows, Icons, Menus and Pointers (WIMP)
Advantages of GUI
- Quick and easy to enter commands.
2. Less chance of errors.
Disadvantages of GUI
- Smaller range of commands can be used.
2. Uses more computer power.
Types of Computers
- Personal Computers (Networked or Standalone)
- Laptops
- Tablet Computers
- Smart Phones
Personal Computers
Found in schools, at home or offices.
They are made of input, storage and output devices grouped in a base unit.
Standalone PC
They are used by one at a time and can function without beng connected to other PCs.
Networked PC
They are connected to other computers in a network in order to share resources and data.
Laptops
Portable computers with LCD screens that are small enough to sit on your lap.
They can be used as standalone and be taken to different places thanks to the built in battery or as networked with the same purpose as Networked PCs.
Advantages of PCs compared to a laptop
- Better components for the same price.
- Cheaper because components are easier to make.
- Larger keyboard, easy to use.
- Design allows heat to escape.
Disadvantages of PCs compared to a laptop
- Large and bulky, not portable.
- Need a contant power supply.
- You cant work with them in different locations and need to copy files to work with them somewhere else.
Advantages of Laptops over PCs
- Smaller and lighter, portable.
- Components use low power.
- Reachargeable battery.
- Usually have built in WiFi to access the internet.
- No need to transfer files to work with them somewhere else.
Disadvantages of laptops to PCs
- Limited battery life.
- Small keyboard.
- Prone to theft.
- Dont have a design for heat to escape.
Tablet Computers
Hand held mobile computers that have a touch screen and a few physical buttons built in.
They may come with a SIM card slot to make phone calls and send texts.
Normally they have built in WiFi and some sensors like cameras and microphone.
They are used to access the internet, view multimedia and use apps.
Advantages of Tablets over laptops
- Smaller and lighter.
- Touchscreen can be used to draw with a stylus.
- Has built in camera(s)
- Has longer battery life.
Disadvantages of Tablets compared to laptops
- Less storage space.
- Not as powerful and slower performance.
- Keyboard is harder to use because it is smaller.
- Touch screen is hard to use for detailed tasks.
Smart Phones
They are mobile phones that are able to perform other tasks apart from making phone calls and texting.
They have touchscreens or physical built in keyboards and usually have digital camera, GPS navigation, wireless WiFi and Bluetooth connection.
Avantages of Smart Phones over tablets
- Smallest of computers, very portable.
- Some have physical integrated keyboards.
- Generally cheaper
- Practical for making phone calls and texting.
Disadvantages of smartphones compared to tablets.
- Very small screen
- Not as powerfull
- Lower battery life
- Very small and easy to be misplaced or stolen.
