Commands tell the PC what to do with the data we provide. In our first programming example (add.ex), the commands were '?' and '+,' and the data was the two numbers.

? is a command meaning "print"
+ is a command meaning "add"
23489 is numeric data
1293374 is numeric data

Essentially, commands tell the computer what to do. Data tells the computer what to do it to.

Euphoria has a provision for storing data in items called variables. A variable is simply a container of data. Just as a bucket would hold water, a variable holds a value. For example, this command set

integer x
x = 5

stores the value 5 in the variable x. (A variable is so named because its value can change.) We could then do things with x, such as

? x + 1

Can you guess what the output would be? If you're not sure, create a Euphoria program file and find out!