Sequence Selection Iteration

2. Sequence

Sequence in a computer language means that programming statements are set out one after another. Unless the computer is told otherwise, it will carry out each instruction in turn.

Therefore a 'sequential language' such as Python or 'C' sets out source code instructions one after another.

In pseudocode, each instruction is set out like this

                           Do this
                           Next do this
                           Then do this 
                           ....

Once translated into a sequential programming language, it may look more like this:-

                         x = 3
                         MyVariable = 34
                         New_Variable = x + MyVariable

Usually the order of a sequence is important. For example the pseudocode below cannot work because New_Variable is trying to use MyVariable and x before they are given a value

         
                         New_Variable = x + MyVariable               
                         x = 3
                         MyVariable = 34