# Data representation

## What is it?

Computers are amazing devices that enable people to do a wide variety of things with them. People can use them to view information, listen to music, play games and more. In order for computers to work, they must represent the information in some way. All data that is stored within a computer, and transferred from or to a computer, is transmitted as a series of electrical signals that are either on or off.

To process data, whether it be text, images or sounds, the computer must convert the information into binary form. The binary number system is a base-2 number system. This means it only has two numbers: 0 and 1. All information in a computer (words, pictures, movies, sound) is stored and transmitted as sequences of bits, or binary digits.

### Australian Curriculum definition

#### Data representation

In Digital Technologies, discrete representation of information using number codes. Data may include characters (for example, alphabetic letters, numbers and symbols), images, sounds and/or instructions that, when represented by number codes, can be manipulated, stored and communicated by digital systems. For example, characters may be represented using ASCII code or images may be represented by a bitmap of numbers representing each 'dot' or pixel.

### Level F - 2:

Recognise and explore patterns in data and represent data as pictures, symbols and diagrams (ACTDIK002)

Collect, explore and sort data, and use digital systems to present the data creatively (ACTDIP003)

### Level 3 - 4:

Recognise different types of data and explore how the same data can be represented in different ways (ACTDIK008)

Collect, access and present different types of data using simple software to create information and solve problems (ACTDIP009)

### Level 5 - 6:

Examine how whole numbers are used to represent all data in digital systems (ACTDIK015)

Acquire, store and validate different types of data, and use a range of software to interpret and visualise data to create information (ACTDIP016)

### Level 7 - 8:

Investigate how digital systems represent text, image and audio data in binary ACTDIK024)

Acquire data from a range of sources and evaluate authenticity, accuracy and timeliness (ACTDIP025)

Analyse and visualise data using a range of software to create information, and use structured data to model objects or events (ACTDIP026)

### Level 9 - 10:

Analyse simple compression of data and how content data are separated from presentation (ACTDIK035)

Develop techniques for acquiring, storing and validating quantitative and qualitative data from a range of sources, considering privacy and security requirements (ACTDIP036)

Analyse and visualise data to create information and address complex problems, and model processes, entities and their relationships using structured data (ACTDIP037)