Interfaces

Interfaces

1. The human-computer interface (HCI)

   • The boundary where the computer and the user meet
   • Commonly referred to as user interface
   • Determines the way that the user interacts with the computer
     • Gives instructions about what is wanted

2. The design of a user interface for a piece of software takes into account the expected ICT skills of the users

   • Software companies design user interfaces
     • To make their programs as easy to use as possible
     • To make the different programs they create as similar as possible
     • So that users are familiar with the way they work

3. Main types of Interfaces

   • Command-line interface
     • Users type instructions using a special set of words and symbols
     • This is the interface used in the early days of computing
     • Only suitable for skilled ICT users
       • As the instructions need to be known
   • Menu – driven interface
     • A menu of options is displayed
       • The user selects one of them
     • This is more user-friendly than a command-line interface
       • As the options do not have to be remembered
   • Graphical user interface (GUI)
     • Small pictures are used
       • To represent options that the user can select
   • Voice interface
     • A microphone is used
     • Into which the user speaks a command to the computer
     • Sophisticated software analyses the voice pattern
       • Executes the instruction given
   • Special devices
     • E.g.
       • “Concept keyboards” with overlays places on the keyboards
       • Braille keyboards
       • Touch-sensitive screens
       • Puff-suck switched and foot switches allow input for people with no arm movement