Google has illegally built “monopoly power” with its web advertising business, a federal judge in Virginia has ruled, siding with the Justice Department in a landmark case against the tech giant that could reshape the basic economics of running a modern website.

A U.S. judge's ruling that Google has illegal monopolies in ad technology sets up the possibility of U.S. prosecutors seeking a breakup. Here's what the case involves and what Google owner Alphabet faces from here.

"The U.S. Department of Justice is focused on breaking up all of Google's monopolies and it does not look like they are going to let up. The best course of action would be for Goo