Formula Nomenclature

For example, in this formula =OFFSET (A1,1,2):  In the parentheses is a reference to Cell A1, but what do 1 and 2 refer to?  Are there rules as to which number goes before others?  Such as number 1 referencing a Row and number 2 referencing a Column?  Or add a number or reference another Cell?  I Appreciate any help here!