PEMDAS is an acronym that allows people to easily remember the order of operations.
In standard format, PEMDAS is the following:
Parenthesis are first. Exponents are second. Multiplication and Division go together, so they are third. And finally, Addition and subtraction go together, so they are forth.
A great way most people remember the acryonym PEMDAS is with the following expansion: Please Excuse My Dear Aunt Sally.
Hope this helps.