Low Level

Question 1

Virtual Machines?

Answer 1

an emulation of a complete computer system which can be used to run alternative operating systems, or several copies of a single operating system.

Question 2

Emulators?

Answer 2

: software which duplicates the function of one computer system in another

Question 3

Mobile Devices?

Answer 3

features which require different types of software from conventional desktop systems eg touchscreen, pinch

Question 4

Vector Graphics?

Answer 4

stored as a collection of mathematically determined shapes or objects; each object in the picture has properties such as width, height, fill colour, line colour

Question 5

Bitmap Graphics?

Answer 5

made up of a grid of pixels and stored in memory as a bit pattern of ones and zeros (calculations are mentioned later in this booklet)

Question 6

Processor?

Answer 6

consists of several different parts: the Arithmetic and Logic Unit which performs calculations; the Control Unit which loads, decodes and executes instructions, and Registers which are small memory locations used by the processor

Question 7

Cache?

Answer 7

a faster kind of memory which stores copies of the data from frequently used main memory locations

Question 8

Read Only Memory?

Answer 8

Permanent memory; data is not lost when power switched off; this memory is very important and is used to store programs, like the operating system, for a long time

Question 9

Random Access Memory?

Answer 9

Memory: used to hold all data required for an active program or application to run; data is transferred from backing storage to RAM and held there until it is no longer required by the processor

Question 10

Address Bus?

Answer 10

identify the address of the location in cache or main memory that is to be read from or written to; uni-directional

Question 11

Data Bus?

Answer 11

will transfer data to/from the address that is held on the address bus; bi-directional; the amount of data that can be carried by the data bus depends on the word size (width of the data bus)

Question 12

Interfaces?

Answer 12

used to allow peripheral devices and hardware to connect to a computer system; allow for differences in speed and the way that data is handled by each peripheral device; an example is a USB; responsible for voltage conversion, status signals, data format conversion