It’s been 15 years in the making, but Illinois is about to see some major gambling changes.

Illinois lawmakers passed a comprehensive gambling expansion bill Sunday afternoon that will dramatically change the landscape for both Chicago and across the state.

So what does it mean? Here’s what you should know.

What is included in the expansion?

The complex sports gambling bill has been drawing attention from all corners of the political world—calling for slots at O’Hare and Midway airports, along with horse racetracks. College teams, however, are said to be exempt and the licensing fees would start in the millions.

The bill would give Chicago a new casino license to be privately owned. In addition, it grants a casino license to the south suburbs and Waukegan.

Thousands of gambling positions would be added to existing casinos as well as to horse racing tracks.

The sports betting plan capitalizes on a U.S. Supreme Court ruling last year that ended Nevada’s monopoly on sports-betting. It languished until this week when Blue Island Democratic Rep. Robert Rita added a long-discussed measure to expand nearly 30-year-old casino gambling.

What will the casinos look like?

Six casinos were authorized in Chicago, Waukegan, the south suburbs, Williamson County, Rockford and Danville.

All casinos can have up to 2,000 positions and can be land-based, the legislation states. In Chicago, the casino can have up to 4,000 positions.

In addition, slots will be allowed at O’Hare Airport and Midway Airport.

What’s next?

The state initiative now must be signed by Gov. J.B. Pritzker. The governor has said he plans to sign the bill, but details on when remained unclear.

“Together, we just accomplished one of the most ambitious and consequential legislative sessions in this state’s history,” Pritzker tweeted Sunday evening

Where will the money go?

Licensing fees and tax revenue could generate as much as $700 million in the first year. It’s intended to be used for the state’s $45 billion capital-construction program.

In Chicago, tax revenue from the new casino will be divided into thirds. The city would get a third and the rest will be split between the state and the private owner.