About Cell Comments
To explain data or provide background, you can add comments to a cell or to a range of cells across multiple dimensions.
To add and view comments, click a cell (or select a cell range), then the Data tab, and then Comments . A small triangle in the upper right of a cell indicates that it has a comment.
You can also view comments in a PDF file or a printed report.
Note:
Forms 2.0 does not support adding comments or attachments to formula cells.