Computer systems do not understand human instructions, nor can they perceive real-life data in its raw form. Therefore, computer systems require a way to store and represent information in an accessible way. They use software and hardware components combined to help retrieve information, store it, manipulate it, and convert it back to a human-accessible format. If you want to learn how computer systems perform complex tasks such as storing and manipulating textual data, videos, music, images of your cat, and much more, this course is meant for you.

Information Representation in Computer Systems

## Input devices
An **input unit** is any device that retrieves data from the real world and converts it into binary data. A few examples of input units include:

* A keyboard that converts character keys into ASCII or Unicode.

* A video camera that converts light into #key# pixels: In digital imaging, a pixel, pel, or picture element is a physical point in a raster image, or the smallest addressable element in an all points addressable display device; so, it is the smallest controllable element of a picture represented on the screen. #key#. 

* A microphone that converts sound waves into electrical signals.

# Input devices
An **input unit** is any device that retrieves data from the real world and converts it into binary data. A few examples of input units include:

* A keyboard that converts character keys into ASCII or Unicode.

* A video camera that converts light into #key# pixels: In digital imaging, a pixel, pel, or picture element is a physical point in a raster image, or the smallest addressable element in an all points addressable display device; so, it is the smallest controllable element of a picture represented on the screen. #key#. 

* A microphone that converts sound waves into electrical signals.

In this lesson, you will be introduced to the workings of input and output devices.

Computer basics

Hardware and Software Components of a Computer

Data Representation in Python

Image, Audio, and Video Representation in Python

Data Compression

Input and Output Devices

Input devices