Understanding what a program is

The first step in understanding how to write a program is to understand what a program is. The technical term for a program is algorithm. For the inexperienced, the term algorithm is ambiguous and, for some, scary. However, an algorithm is simply a set of steps. This means the most literal way to think of a program is as a series of steps that a computer or other programmable device will carry out to accomplish a task.

To demonstrate what an algorithm is, consider the steps it takes to withdraw money from an ATM:

1. Enter the debit card into the machine.
2. Enter the PIN.
3. Enter the amount to withdraw.
4. Remove the debit card from the machine.
5. Take cash and go.

The steps it takes to withdraw money from an ATM is a prime example of an algorithm. Now that we know what an algorithm/program is, what purpose does it serve?

What is the purpose of a program?

The purpose of a program starts with a problem to solve. For our purposes...