1. Input, Output and Processing

2. An ICT System
In general terms, ICT systems take an input, and process it to produce an output.
Process
Input
Output
These different functions are performed by different pieces of hardware.
Processing also requires some software.

3. Hardware & Software
Hardware is the physical components that make up a computer system.
Software is the programs and data that make the hardware do something useful.

4. Input Devices
Input devices are used to get data into the computer, and include:
Keyboard
Pointing devices
Scanners
Cameras
Microphones
Graphics tablets
Touch screens

5. New Input Devices
Lots of new devices – tablets, sat-navs, smart-phones, etc. – have touch screens
What are the implications of this?
Designers need to re-think some things that they’ve been doing for years:
Rollovers, drop-down menus, etc. on web-sites won’t work
“Drag and Drop” - how does the screen know whether you’re dragging or scrolling?

6. Output Devices
Output devices are used to get information out of the computer, and include:
monitors
printers and plotters
speakers and headphones
computer controlled manufacturing devices

7. Processing Devices
Processing devices are the “engine” of the computer. Processing takes place in:
central processing units (CPUs)
graphics cards (GPUs)
maths co-processors
Modern processors often have multiple cores, which means that they have several processors on the same chip.

8. Types of Software There are three basic categories of software:
Operating systems
Applications
Bespoke or off-the-shelf
Suites and integrated packages
General purpose
Utilities
Monitoring & communication software
Security – e.g. anti-virus & firewalls
Programming – e.g. compilers & interpreters

9. Software and Input/Output
The processing of creating software is called programming
When you learn to program, the first thing you learn is usual to create some output – e.g. to display your name or Hello world on the screen.
You will also want to learn to accept input from the user quite early on, e.g.
to ask questions or to give choices
to use as the controls for games, etc.
We will be looking at input and output using both Scratch and JustBasic later in the year.