# Data Types / Binary Flashcards

primitive data type

a basic data type provided by the programming language as a basic building block

types of primitive data types (5)

- integer
- real/float
- boolean
- character
- string

denary

base 10 number. uses the combination of ten symbols to represent any number

binary

base 2 number. uses the combination of 2 symbols (0 or 1) to represent every number

hexadecimal

based 16 number. uses the combination of 16 symbols (10 numbers and 6 letters) to represent every number

why use hexadecimal?

- easier to read/ remember
- quicker to write/type
- less chance of making an error
- easy to convert

uses of hex

- define colours
- in MAC addresses
- in assembly language and machine code

integer

any positive or negative whole number e.g. 3, 0, -14

real (floating point)

a positive or negative number with a fractional component e.g. 0.002 or -1.98

character

Any single letter, symbol, number, character or control character

string

any combination of letters, symbols, numbers, characters or control characters e.g. Hello, £4.56

Boolean

Any true/ false data types which often represent logical situations

Sign magnitude most significant bit

represents + or -

+ = negative

- = positive

0.1

positive

1.0

negative

fixed point binary

positive of the binary point is fixed on the number line

by changing the position of the binary point you can…

increase the size of the number

increase the accuracy of the number

mantissa

the actual number you want to store

exponent

positive of the binary point is fixed on the number line

how to convert floating point binary to denary

1) First work out the denary number in the exponent which tells us that the binary point moves ‘n’ places to the right

2) Write out a new binary weighting line with the point in the right place and then convert into denary

Binary -> denary positive exponent

right

Binary -> denary negative exponent

left

in two’s complement the sign is stored in

the most significant bit

normalising a number

means that there is only one way to represent the number