2.1.9 Data Representation Flashcards
Bits
A small singular digit.
Byte
8 bits placed together.
Binary
A collection of 1s and 0s to store data.
Or
Format in which numbers are transmitted and calculated in a computer system.
Hexadecimal
Hexadecimal is a numbering system with 16 symbols. Base 16.
Denary
Ordinary numbers - base 10.
What are the levels of bytes?
Keep Calm = kilobyte
May = Megabyte
Geckos = Gigabyte
Take = Terabyte
Paris = Petabyte
What is a string?
“I love Java”
Integer
No decimal numbers.
Characters
Single characters
Types of characters?
Ascii or Unicode
How are colours stored?
Hexadecimal
What is a double?
Decimal 2dp
What is a float?
Decimals going on forever.
Boolean
True or False.
Which is the biggest for storing?
String
Which is the smallest?
Boolean
Compare Hexadecimal and Binary
Hexadecimal is easier to read and requires less space.
What is sign and magnitude?
When there is a sign representing positive or negative (0 = positive, 1 = negative.)
What is two’s complement?
When there is a sign representing -128. (1 is negative, 0 is positive)
How to convert positive to negative in two’s complement?
Change signs around
Add 1
How to convert negative to positive in two’s complement?
Minus 1
Change Signs around.
What is floating point?
Mantissa and Exponent
M and E
Used for decimals in binary.
What is the Mantissa?
Actual Number
What is Exponent?
Position of decimal point.
If the mantissa or exponent start with one it is a…
negative
