Defining control flow and its tools

Simply defined, control flow is the order in which an algorithm reads and executes instructions, functions, and statements. Control flow means the computer will make a decision. Think about it this way: when I go outside my building, I'll either use an umbrella or I won't use an umbrella. That depends on whether or not it is raining (and whether or not I remembered my umbrella, I guess). Depending on that condition, we make a decision. That process is the control flow process in algorithm design.

Let's look at some of the control flow statements available in the Python programming language:

• while
• if
• for
• range()
• break
• continue
• list comprehensions
• The pass statement
• The try statement

These tools allow the algorithm to do things such as run so long as a certain condition or set of conditions is met, stop or break when a condition happens, continue for a range of values only, and so on...