Introduction

• First computers


  Weighed several tonnes, occupied entire buildings, very rare in the early 1950s (fewer than 100 in the world)
• The notion of portability and the vast range of current uses of computers would have seemed very strange to the people who built and worked with those early machines
• Today, computers and information technologies are practically everywhere in the world around us, and the processing power of an entire 1950s computer can be found on a silicon chip that is hardly visible
• At the time of writing, it is estimated that there are almost 2 billion personal computers in the world
• Ubiquity


  The state of being everywhere, or in many places, at the same time
• The cloud


  A metaphor for the internet, where computing resources and data are stored and accessed remotely
• The binary number system forms the basic building blocks from which computer data and programs are formed
• The pace of change in Computing and IT is accelerating over time