This web page is going to introduce tables.

First row, first column First row, second column
Second row, first column Second row, second column

The problem is, this doesn't look much like a table because there aren't any borders around it.

Now lets take the same table and put the BORDER attribute in the CSS.

First row, first column First row, second column
Second row, first column Second row, second column

You now have tables that are in the center of the screen.