The Formula Bar in Microsoft Excel is a toolbar located above the worksheet grid that displays the formula or value of the active cell. Here are the basic steps to use the Formula Bar in Microsoft Excel:

- Open Microsoft Excel.
- Click on a cell in the worksheet to make it the active cell.
- The Formula Bar will display the contents of the active cell, either as a formula or a value.
- To enter a formula in the Formula Bar, start by typing the equal sign “=” followed by the formula expression. For example, to add the values in cells A1 and A2, type “=A1+A2” in the Formula Bar.
- You can also edit a formula or value in the Formula Bar by clicking on the cell and making changes directly in the Formula Bar.
- To clear the contents of a cell, click on the cell and press the “Delete” key or backspace in the Formula Bar.
- The Formula Bar can be expanded by clicking on the arrow icon on the right-hand side of the toolbar, which will show a larger view of the formula or value.
- You can also hide the Formula Bar by selecting the “Formula Bar” checkbox in the “View” tab of the Ribbon.

The Formula Bar in Microsoft Excel is a useful tool for entering and editing formulas and values in cells. By using the Formula Bar, you can ensure that your formulas are accurate and free of errors.