Like input-output symbols, process boxes have a single line connecting it to the previous flowchart step and a single line leading to the next one. A flowchart may contain any number of process boxes.

Data types, structures and operators - Edexcel Input/output and validation. Programs use data, known as ‘values’. Variables hold values. Each variable in a program must have a data type.

Entering data into a program is referred to as data input. Input can come from many automated sources, but the most common is keyboard input from the user.