Why rowspan and colspan attributes are used?

ROWSPAN is used to combine the cells vertically. It merges the number of cells vertically and displays them as a single cell.

E.g. <TD Rowspan= "3"> where 3 is the number of rows that the cells span across.

COLSPAN is used to combine the cells horizontally. It specifies the number of columns that the cells span across and shows them as a single cell.

E.g. <TD Colspan= "4"> where 4 is the number of columns that the cells span across.