In programming, variables are placeholders for information you would like to store and use later. Variables are very common in algebra; for example, if we use x as a variable to store the value 3 (x = 3), then later we can recall this value 3 simply by recalling the variable x.

 

We can also use variables to perform calculations. For example, 2 * x will return the value 6.

 

Finally, we can replace the value of a variable. That is, if we set x = 4, then the same calculation, 2 * x will return the value 8.