what is div tag and thier use

what is a div tag?

using div tag we can logically divide a page

to devide a page we use iframe and this is old method and also some restrictions.
to divide page logically and use freely
then we use div tag and div tag having two arguments id and class you can specify your manner to use the program.

eg:

<div class="tem" id="tem1">

</div>

using css we can move div tag in any space in the screen

using:
#tem1{
position:absolute;
}
thank you.