The function screen tip is a small window that appears when you click into a function in the formula bar. Although this window looks quite simple, it is actually a very useful tool when editing and debugging Excel formulas.
When the function screen tip is visible, you can use it to precisely navigate the function arguments in a formula. The window is context-sensitive and its contents depend on the function the cursor resides in. As you move the cursor through a formula, the currently active argument is bolded. If the cursor is moved to a different function in the same formula, the arguments for that function are displayed.
If you click directly on the argument name, the text that makes up that argument will be selected. This is a powerful way to copy and paste into a formula without bringing in extra characters, or accidentally truncating an important character.
Finally, if the function screen tip window is in your way, you can move it to a new location using the four headed arrow.
