The reference to a cell range is defined by referencing its two corner cells:

•Starting cell: The upper-left cell of the range.

•End cell: The lower-right cell of the range.

The starting and end cells are separated by the : operator. For example, B4:D6.

If the R1C1 style is selected for cells referencing, in some cases you don't need to use the : range operator. For instance, if you want to reference the range of all cells of one row, you can only specify a reference to this row (that is, the R1 reference refers to the range of all cells of the first row).