Resizing Automatic Reformatting

What is the difference between the HTML <table> and ASP <asp:table>? I've just shifted development environments from DreamWeaver to Visual Studio. I've put together a page by dropping elements directly onto the grid, but I get no automatic reformatting. My old technique from DW would be to put it all in a table for formatting, but I find that clumsy in VS.

First, they have both html and asp table controls, and I don't know the difference between them. Second, the two controls are rendered on the design page differently, and I really can't tell what they are going to do. Third, the asp:table is shown without any rows or columns. What's up with that?