CHICAGO — On a huge outdoor stage on a hot Saturday afternoon, a band called Go! Team did its best indie-rock cheerleader impression for a crowd of thousands.

Just 200 yards away, another crowd inside an air-conditioned tent watched the New York Mets on TV, blogging, charging cell phones. Despite the gigantic music festival raging outside, you wouldn't have known it, except for a flat-screen TV showing a live feed of the festival and another recapping musical highlights from the day before.

That's Lollapalooza in the age of interactivity, when fans can experience the festival without actually going, and bloggers attended the fest without actually experiencing it in person.

Interacting with music once meant going to a concert, or playing an instrument, maybe forming a band. The digital age, though, has altered the way America consumes popular culture — and music in particular.

Now, actually seeing a band play live is only one part of a concert.

Lollapalooza this year in Chicago was a marvel of high-tech connectivity. The festival's Web site offered concertgoers the opportunity to customize the schedule, e-mail it to friends and download it to an iPod (though it was easier and faster to print out the schedule grid, circle the good stuff and have an actual conversation about what bands to see and when).

A promotion with Apple offered an iTunes sampler of songs by bands playing the festival, which took place Aug. 4 to 6. The computer company also handed out gift cards on the grounds good for $20 worth of Lolla-related music from the iTunes music store.

There were tech-based promotions — for example, see a Lolla poster around town, take a picture with your cell phone and send it as a text message for the chance to win tickets.

At the festival was a cell- phone-based scavenger hunt involving clowns, just in case 130 bands on eight stages over three days failed to hold your attention.

If your focus wandered (or you wanted to check out the smaller, lesser-known bands), you didn't have to miss anything — one of the sponsors, AT&T, offered free live webcasts of the big acts, which are also archived on its "blue room" Web site for after-the-fact viewing (http://blueroom.att.com).

And the official Lollapalooza Web site (www.lollapalooza.com) featured a message board where fans dissected the day's performances. The Web site received more than 2 million hits during the three-day festival, which was attended by about 50,000 people, a publicist said.

Lollapalooza was the latest example of technology at work in music, but far from the only one.

The annual South by Southwest Music Festival in Austin, Texas, has for the past few years posted songs by bands playing the music-industry conference on its Web site (www.sxsw.com); MTV steers viewers to its Web site for music videos, reserving most of its on-air programming for reality shows; digital music files are the preferred format over CDs for younger listeners; and independent Weblogs featuring MP3s have piqued the interest of record labels, which now pitch artists to bloggers for inclusion on their Web journals.