In programming, a loop is a series of commands to be executed repetetively. Typically, there will be some exit condition (checked at every iteration or pass of the loop). (If there is no condition, or it never occurs, you get an infinite loop.)
If a specific variable is advanced through certain important values (predeclared or calculated as needed) every run of the loop, this is often referred to as a for loop (or foreach, if you can only give it the complete list of values). If there is just the condition, but no singled-out variable, this is a while loop, or a repeat until loop. You could also loop by using a jump or goto, if you were so minded and your programming language offered those.