Conditional branching is one of the most fundamental principles in programming. Most programmers do it without thinking about it.

The great power of a computer program is not just to compute data, but to compute data in different ways depending on the qualities of the data. Conditional branching is about a program making decisions on the fly, based on the data its given.

All conditional statements - or conditionals - evaluate to either true or false. Once the evaluation has taken place, the computer performs the relevant action.

Consider this pseudocode (pseudocode isn't quite English, and it isn't quite a programming language - it's a way of expressing algorithms).

Get date from user.
If date = 25th of December
  Print Hurrah, Christmas Day!
  Print What a boring day!

See that? That's conditional branching. The program got data, and then it executed different instructions based on what the data was. If date = 25th of December evaluated to true, it printed a seasonal greeting. Otherwise, it printed "What a boring day!". You can see how much more useful this is than a program that executes the same instructions every time!

Common keywords used in conditional brancing are if and switch, along with their partners else and case.

Log in or register to write something here or to contact authors.