Merge in MS Excel?

Guys
I use a lot this function "Merge" in MS Word documents to show differences between files.
Does anybody know if same or similar function exist in MS Excel?
thanks!

Guys,
me again. Anyone knows about a way of doing a comparison between 2 MS Excel files?

You easily do this with the following steps:
1.Open your sheet
2. go on the top then you see review after clicking review you see compare click on this.
3.Browse a Excel Sheet which you want to attach.
4. Select your document click on more button.
5.Then after click OK to merge document,
6.Accept the changes.