PPE 2 Revision Flashcards
A computer has 1024 megabytes of RAM.
How many gigabytes of RAM does the computer have?
1.204 (divide number by a thousand)
Name two items that will be stored in the RAM.
- The Graphical User Interface (GUI).
- The software applications.
- Operating systems.
What is the difference between ROM and RAM?
ROM is memory that cannot be changed by a program or user. ROM retains its memory even after the computer is turned off. RAM is a fast temporary type of memory in which programs, applications and data are stored.
What is an embedded system?
A computer which forms part of an electronic device.
How can the reliability of a system by assessed?
Rigorous testing.
Explain the difference between proprietary and open standards.
Proprietary standards are owners and maintained by corporations, where as open standards are publicly available and modifiable.
What is the purpose of the CPU?
It processes data and executes instructions.
What is meant by clock speed?
The clock speed is the number of operations that the processor can carry out per second. It is measured in the unit of hertz.
What is virtual memory and why is it used?
Virtual memory is temporary space taken up on the hard disk to store programs and data that are currently in use. It is used when the RAM runs out of space to deal with all the demands of the computer.
Using an example for each, explain the difference between primary and secondary storage.
Primary storage is volatile. When the computer is turned off, the contents are lost. Two types are RAM and cache memory.
Secondary storage is non-volatile, so it can retain data even when the power is off. Examples are hard drives and USB sticks.
What is the purpose of cache memory?
- It is fast memory located very close to the CPU.
- It allows CPU to access data fast to speed up processing.
Name three input devices.
- Keyboard.
- Microphone.
- Sensor.
Name three output devices.
- Printer.
- Speakers.
- Monitor.
What is meant by an over flow error.
Overflow occurs when the largest number a register can hold is exceeded.
What is the purpose of html?
HTML is standard language for describing the structure and presentation of information via the Internet.