Unlike word processors, in spreadsheets you do not enter information directly on to the page. Instead, you type into the formula line at the top of the window. When you have finished typing or editing, you click the Tick button and the result appears in the cell.
When you are typing in the formula line, you will see that the pointer changes to a caret and that the buttons in the toolbar are greyed out, as in the previous screen.
See the following for details of types of data you can enter: