Comments are annotations that you and other document reviewers can add to a document. These notes can be viewed on screen but don't print unless you want them to.
Select the cell for which you want to insert a comment (Figure 5).
Figure 5. Start by selecting the cell you want to enter a comment for.
Choose Insert > Comment (Figure 6).
Two things happen: A comment marker (a tiny red triangle) appears in the upper-right corner of the cell and a yellow box with your name ...
Figure 6. Choose Comment from the Insert menu.