The F2 function key lets you quickly and easily edit a cell's data by activating Excel's edit mode and placing the insertion point at the end of the active cell's existing contents. Here's how to use the F2 key to edit cells.

This example shows how to edit a formula in Excel

Enter 4 in cell D1, 5 in cell D2, and 6 in cell D3.

Select cell E1 to make it the active cell.