The Font Group contains a variety of buttons that allow you to quickly apply formatting to selected cells.
The tools within the Alignment Group will change the position of the characters within a selected cell or cells.
The Number Group allows you to change the formatting of numbers for values in selected cells.
Only the cell(s) that has a thick border around it is active or selected.
To select more than one cell in a rectangular area, click and drag the mouse. The range of cells selected is the address of the top/left cell through to the address of the bottom/right cell. The selected cells will have a thick border around them; all but the first cell will appear with a slightly shaded background.
To select random cells, hold the Ctrl key while clicking desired cells.
To select a blocked range of cells, columns or rows, select one cell/row/column, hold Shift key & select ending cell/row/column
To select an entire column, click the corresponding column letter; the mouse pointer appears as a black arrow.
To select an entire row, click the corresponding row number.
To select an entire workbook, click the box above row 1 and to the left of column A.
You can also use the following keyboard methods: