Sequence

The simplest form of program flow is sequencing. This simply means that the instructions in the code are executed one after the other.

For example:

PRINT("Input a value for x")
INT x = INPUT()
INT y = x*x
PRINT(x)

This code simple asks for a value, inputs it, calculates its square, and prints the result.

Very few programs are as simple as this. But most programs contain sections of purely sequential code.