The Red Hot Chili Peppers are among the big names listed to headline this year's Lollapalooza music festival in Chicago. The Black Keys, Jack White, Avicii and Florence and the Machine have also been tapped to headline the three-day gathering, as Jane's Addiction lead singer and Lollapalooza founder Perry Farrell announced the lineup on Wednesday.

Every year it's kind of a nail biter putting a lineup together, Farrell said, according to the Associated Press. There were moments when I looked at it and I was beside myself. I didn't know what to do.

Set to kick off on Aug. 3 in Chicago's Grant Park, the festival's schedule features more than 120 bands, including a unique mix of mainstream headliners, indie rock bands and innovative EDM DJs.

One surprising inclusion in the Lollapalooza 2012 lineup is Black Sabbath. The headlining spot marks the band's only North American gig of 2012, as they were tapped to headline this year's Coachella but were forced to pull out when band member Tony Iommi was diagnosed with lymphoma.

With the long-time Sabbath guitarist having recently completed his chemotherapy, band manager (and frontman Ozzy Osbourne's wife) Sharon Osbourne contacted Lollapalooza organizers to accept a previously made offer.

They mean so much to me, and they mean so much to music in general, that I kind of feel like I'm dreaming to know that Black Sabbath is actually gonna perform at Lollapalooza, Farrel said, in an interview with Rolling Stone.

Rounding out the bill are recently reunited At the Drive-In, Miike Snow, Bloc Party, Franz Ferdinand, Delta Spirit, Metric, Gaslight Anthem, Sigur Rós, the Shins, Kaskade, Bassnectar, J. Cole, Childish Gambino, and another big reunion in the Afghan Whigs.

As 2011 will go down as the summer that EDM invaded Lollapalooza, the 2012 lineup doesn't shy away from the challenge of following up with a bigger and better dance party.

EDM heavyweights Avicii and Justice are both slated to headline the show -- a privilege that they say they never saw coming.

I knew that I was playing it; I didn't think I was gonna headline, and then I found out I was headlining, Avicii tells Rolling Stone. It's a lot of pressure, but I'm really psyched about it and I think it's gonna go down really well.

With two acts on both ends of the age spectrum -- Black Sabbath and Avicii -- it seems as if Lollapalooza 2012 is looking to set the standard as a festival for music fans of all ages.

What you have is three to four generations -- maybe five generations of people, counting Kidsapalooza -- that are all going to a place in peace, to experience music and learn to like and understand and love each other, Farrell says. And this is one place where I can say the generation gap doesn't exist.

With last year's festival having sold out at 270,000 festival-goers over the three-day event, discounted souvenir and early bird three-day passes for the 2012 event have already been depleted. Regular priced $230 passes are still available through the Lollapalooza 2012 website.

For a full full list of performers, check out the Lollapalooza 2012 lineup announcement video below.