To make your buttons more accessible from the keyboard—especially if you've got a lot of them—you can use the TabStop and TabIndex properties. Here's what those properties do:
TabStop indicates if this button can accept the focus when the user tabs to it.
TabIndex is the index of the current button in the tab order (starts at 0).
When the user presses the Tab key, the focus moves from button to button, ascending through the tab order.
Another use of Tab order is in text-entry forms. If, for example, you have 10 text boxes in a row that need to be filled out, the user can enter text in the first one, press Tab to move to the next one, enter text there, press Tab again to move to the next text box, and so on. Thoughtfully setting the tab order in such a case can make text-oriented forms much easier on your users.