1. HardwareHardware F451 - AS Computing

2. Hardware and Software Definition Hardware –The physical components that make up a computer system. Includes all input, output, storage devices Definition Software –The computer programs that tell the computer what to do.

3. Input & Output Definition – Input Device –Hardware used to put data into the computer Definition – Output Device –Hardware used to presents data from a computer

4. Other input and output devices

5. Operating a Computer INPUT PROCESS OUTPUT

6. Data and Information Data –Raw Facts and Figures –No structure or context Information –Structured, Organised Data –Processed Data

7. StorageStorage Definition – Storage Device –Permanent and Temporary. Hard disk & RAM –Hardware device used to store data. A device that can receive data and retain it Definition – Secondary storage Device –A peripheral/external device used to store data eg. Hard disk

8. Types of Secondary Storage Hard Disk –Store files, application programs, OS software CD-Rom, DVD-Rom –Install software CD-RW, DVD-RW –Backup files, Transport Files Memory Stick (do not write USB in an exam. You must say memory stick!) –Transport files between computers

9. HardwareHardware The term hardware refers to the physical components of the computer. Hardware is divided into: –external components (peripherals) –internal components (processing and storage).

10. External components The term external components refers to the parts that you physically interact with. These are also known as peripherals or input/output devices and include the: –keyboard –monitor –printer

11. SensorsSensors A sensor is an input device that detects physical quantities. Eg. Heat (Thermistor), Light, Sound, Movement Used in cars, burglar alarms, fire alarms Software must be used to control a sensor and act on the input

12. ActuatorActuator Device which can be operated by a computer which produces physical movement eg. electric motor or turning a valve on or off Used in large central heating or air conditioning systems

13. Internal components The term internal components refers to the components contained within the casing of the computer. They include the: –processor –memory (RAM and ROM) –hard disk.

14. Types of Memory Random Access Memory (RAM) Immediate access store (IAS) It temporary stores data used by applications that are running. The contents are lost when the computer is switched off. VolatileVolatile Random Access Memory (RAM) Immediate access store (IAS) It temporary stores data used by applications that are running. The contents are lost when the computer is switched off. VolatileVolatile Read Only Memory (ROM) ROM is a permanent storage area which cannot be changed by the user. ROM contains the start up software (this makes the PC boot up) Non-VolatileNon-Volatile Read Only Memory (ROM) ROM is a permanent storage area which cannot be changed by the user. ROM contains the start up software (this makes the PC boot up) Non-VolatileNon-Volatile

15. Read Only Memory Non-Volatile – Contents of memory is not erased when hardware is powered off. Start upContains Start up program Start up program is required immediately when power is switched on

16. Random Access Memory Volatile – Contents of memory is erased when hardware is powered off Contains applications software currently being used, OS files Allows changes to be made to saved contents Fast access to data