The Alt+Enter shortcut isn't limited to new formulas you write—you can go back and clean up any messy formulas at any time.

The text trap: If you select numbers and the status bar stays blank (or only shows the Count), your numbers are formatted as text—and Excel can't sum words! This tells you that you should click the ...

By moving around, some cancer cells force attacking immune cells to just nibble at the edges rather than engulf them ...