Autofill Copy in Excel Spreadsheets

There are some autofill features in Microsoft Excel, which automatically populate cells based on copying data.
If you want to duplicate data down the cells in a column, select the group of cells in the column, including the entry to be copied, and press Control + D.
To duplicate data in cells along a row, select the cells in the row, including the entry to be copied, and press Control + R.
For example, let’s say the number 10 is in cell A1, select the range A1 to A5 and press Control + D, and you will now have the number 10 in the first 5 cells of column A.
These two shortcuts are particularly good for copying a formula across a range of cells.