Digital data
As a human you are constantly processing dataUnits of information. In computing there can be different data types, including integers, characters and Boolean. Data is often acted on by instructions.. This type of data is in analogueAnalogue is a continuous stream of information that can have a range of values form. Analogue data comes in a continuous stream, like sound or light waves. Everything you see or hear is an uninterrupted flow of data to your senses.
Computers are not able to process analogue data. They need data to be in a different, digitalInformation stored as discrete values usually represented as numbers. This contrasts with analogue data which is represented by continuous data, usually in waves. form. Any data we want a computer to process must first be converted to digital. Digital data is made up of binaryA number system that contains two symbols, 0 and 1. Also known as base 2. digits.
The circuits in a computer processor are made up of billions of transistors. A transistor is a tiny switch activated by the electronic signals it receives. The digits 1 and 0 used in binary reflect the 'on' and 'off' states of a transistor.
Bits and binary
The number system we use every day is called decimal, denary or baseThe number that is going to be raised to a power 10, as there are ten possible numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
The number system that computers use is called the binary or base 2 number system as there are just two possible numbers. Only the digits 0 and 1 are used to store data. A binary digit, or bitThe smallest unit of data in computing represented by a 1 in binary., is the smallest unit of data in computing.
A bit is represented by a 0 or a 1. Binary numbers are made up of binary digits (bits), e.g. the 4-bit binary number 1101 is 13 in decimal while 1101.101 is 13.625 in decimal.
Data types
Data can be stored in many different formats called 'data types'. Common data types are described below:
Data type | Description | Example data |
Integer | Whole numbers only | 0, 1, 2, 3 |
Real/Float | Numbers that can have a decimal part | 0.1, 1.2, 3.4 |
Boolean | Two values only - 'true' and 'false' | True/False, 1/0, Y/N |
Character | A single letter, number or symbol | A, B, C, @, * |
String | Used for text 鈥 can include any character | Digital Technology |
Date/Time | Used for dates and times | 20:55, 29/11/2016 |
Data type | Integer |
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Description | Whole numbers only |
Example data | 0, 1, 2, 3 |
Data type | Real/Float |
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Description | Numbers that can have a decimal part |
Example data | 0.1, 1.2, 3.4 |
Data type | Boolean |
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Description | Two values only - 'true' and 'false' |
Example data | True/False, 1/0, Y/N |
Data type | Character |
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Description | A single letter, number or symbol |
Example data | A, B, C, @, * |
Data type | String |
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Description | Used for text 鈥 can include any character |
Example data | Digital Technology |
Data type | Date/Time |
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Description | Used for dates and times |
Example data | 20:55, 29/11/2016 |