You can put data inside each cell, the data can be anything you want, like: number or text.
You can apply your own styling on each cell by using menu options.
You can apply formula on a cell by using formula bar.
To apply formula on a cell, the format is => (3C1) or (A1 + B1) or (3*A1 + 9*B2).
Formula bar is on right side of fx.
To add notes click on tools button then click on note.
To save a file click on File button an then click on Save.