Qus: Difference between loop & repeat?
Loop and Repeat both are used to execute child steps.
Repeat : Repeat is a conditional based flow step. The execution of child steps will be depends on "REPEAT ON" value( SUCESS / FAILURE in property panel).
Loop : You should perform a loop operation on array of items(String list/Document list/Object list). Loop operation process each and every array element in the array. you have to give the input array value.