Using Tab index property

For my application I want to define the sequence of the movement through user inetrface screen by using the tab button. What I understood is that I can do this with the tab index property. Can somebody explain me how this porperty works and how to define. I can enter a number. Is 1 the first field to focus on? And what if there is a read-only filed which shouldn't be in the sequence at all? And the consequence with conditional formatting?
1 answers

You can set the tab index by selecting the input fields and set the right order by raising the numbers. For the answer of conditional formatting click here.

Note: Since you can select read-only fields, the tab index doesn't automatically skip them. So for now, you have to set the read-only fields too. But if you end up with an customize save or cancel button, you can also set the tab index on that buttons. In that case, make sure the tab index numbers of the readonly fields are higher than the numbers of the customized buttons. The user wouldn't probably tab to the read-only fields.