A mouse pointer shows you where you are within a program and will change shape depending on where you move the mouse, for example, when you are using a word processor program and you move the mouse to the top of the page on to the menu bar it will turn into an arrow.
Once a productivity program has loaded you are ready to enter data. In the case of a word processor the data will take the form of words that you type to create the required document, for example, a shopping list.
In a word processor, the place on the blank page where your data will appear is shown by a flashing bar (|) called the Insertion Point. Some people call this the Cursor. You can use the mouse to move the pointer to anywhere in the document and the pointer turns into an I bar. When you click the mouse button the Insertion Point will be where you clicked.