1.3. Why Most—But Not All—Tables Are Bad
Why are tables such a bad idea as a design mechanism? There are numerous reasons, but the ones we're most concerned with in this context are:
They result in load times that are longer than necessary.
They encourage the use of inefficient "placeholder graphics" that further slow performance.
Their maintenance can be a nightmare in which even minor changes "break" the entire layout.
1.3.1. Tables Mean Long Load Times
Most people don't know that Web browsers are deliberately designed to ensure that each table downloads as a single entity. So, none of the material that's contained in a table will be displayed until all the contents of that table are downloaded to the client machine and available for display. ...