Using the Enter Same Data in Multiple Cells Shortcut
Windows keyboard shortcut
Mac keyboard shortcut
This Excel shortcut enters the same data in every cell when multiples cells are selected. If you frequently use copy & paste this may become your new favorite shortcut.
Cells do not need to be contiguous for this shortcut to work. You can use CTRL on Windows or Command on Mac to select non-contiguous cells.
Other useful Entering Data keyboard shortcuts