(CNN)The term gerrymandering dominates the headlines today, but what do you really know about this political word?
What is gerrymandering?
Gerrymandering is when politicians manipulate voting district boundaries to favor one party over another. In most states, state legislators and the governor control the once-a-decade line-drawing process. So what happens when one party controls the state House, the state Senate and the governor's mansion? The party usually does everything in its power to draw the lines in a way that favors them and puts their political opponents at a disadvantage.
That's called partison gerrymandering, and it's how you end up with oddly shaped congressional districts.
Like in Pennsylvania ...
Or Maryland ...
Or Texas.
And gerrymandering isn't something new that's popped up in this hyperpartisan environment. American politicians have been gerrymandering districts for more than 200 years.
How gerrymandering got its name 01:57
How did it get its name?
The first case of gerrymandering occurred in 1810 in Massachusetts. A salamander shaped district was drawn in the northern part of the state during the term of Gov. Elbridge Gerry. This redistricting plan help Gerry's Republican colleagues hold on to power in the state legislature.
A political cartoon at the time called attention to the odd, salamander shaped district. Gerry and salamander were mashed together in the public's mind, and just like that, the words "gerrymander" and "gerrymandering" were born.
Does gerrymandering cause polarization? 03:34
What does the Supreme Court ruling mean?
It's a big deal.
The justices, in a 5-4 ruling, said essentially that when squabbles erupt over whether politicians have gone too far in drawing district lines for partisan gain, the federal courts must stay out of the dispute.
It essentially gives a green light to politicians of both parties to be as aggressive as they want to be in drawing up districts that benefit their side and hurt their political opponents -- and without fear of the federal courts getting involved. So it would be up to the states -- and the voters -- to rein in such behavior.
It's a sweeping ruling that could alter the balance of power in state legislatures and Congress for years to come.
