After taking a break in 1996, Green Day began to work on a new album in 1997.
From the outset, both the band and Cavallo agreed that the album had to be different from its previous records.
The result was Nimrod, an experimental deviation from the band's standard pop-punk brand of music. The new album was released in October 1997. It provided a variety of music, from pop-punk, surf rock, and ska, to an acoustic ballad. Nimrod entered the charts at number 10. The success of "Good Riddance (Time of Your Life)" won the band an MTV Video Award for Best Alternative Video for the song's video, which depicted people undergoing major changes in their lives while Billie Joe Armstrong strummed his acoustic guitar. The song was also used in the second "clip show" episode of Seinfeld and on two episodes of ER. The other singles released from Nimrod were "Nice Guys Finish Last" and "Hitchin' a Ride" and "Redundant".

In 2000, Green Day released Warning, a step further in the style that they had hinted at with Nimrod. Critics' reviews of the album were varied. All Music Guide gave it 4.5/5 saying "Warning may not be an innovative record per se, but it's tremendously satisfying." Rolling Stone magazine was more critical, giving it 3/5, and saying "Warning... invites the question: Who wants to listen to songs of faith, hope and social commentary from what used to be snot-core's biggest-selling band?"Though it produced the hit "Minority" and a smaller hit with "Warning", some observers were coming to the conclusion that the band was losing relevance,and a decline in popularity followed. While all of Green Day's past albums had reached a status of at least double platinum, Warning was only certified gold.

At the 2001 California Music Awards, Green Day won all eight awards that they were nominated for. They won the awards for Outstanding Album (Warning), Outstanding Punk Rock/Ska Album (Warning), Outstanding Group, Outstanding Male Vocalist, Outstanding Bassist, Outstanding Drummer, Outstanding Songwriter and Outstanding Artist.

The release of a Greatest Hits compilation, International Superhits!, and an assemblage of B-sides, Shenanigans, followed Warning. International Superhits and its companion collection of music videos, International Supervideos!, sold reasonably well, going platinum in the U.S. Shenanigans contained some of the band's b-sides, including "Espionage" which was featured in Austin Powers: The Spy Who Shagged Me and was nominated for a Grammy for Best Rock Instrumental Performance.

In the spring of 2002, Green Day co-headlined the Pop Disaster Tour with Blink-182. Despite the co-headlining title, Green Day would play each show before Blink-182, who at the time were experiencing more success. The tour was documented on the DVD Riding In Vans With Boys.

Kerplunk's underground success led to a wave of interest coming from major record labels, and eventually they left Lookout! on friendly terms and signed with Reprise Records after attracting the attention of producer Rob Cavallo.
Signing to Reprise caused many punk rock fans to regard Green Day as sellouts. After signing with Reprise, the band went to work on recording its major label debut, Dookie.

Sample of "Longview", the first single from Dookie, which combined a memorable bass line with a guitar riff and drums introduced in the chorus.

Sample of "Basket Case", the third single from Dookie, which was about Armstrong's panic attacks.
Released in February of 1994, and recorded in 3 weeks, Dookie became a commercial success, helped by extensive MTV airplay for the videos of the songs "Longview", "Basket Case", and "When I Come Around", all of which reached the #1 position on the Modern Rock Tracks charts.
That year, Green Day embarked on a nationwide tour with queercore band Pansy Division as its opening act. The band also joined the lineups of both the Lollapalooza festival and Woodstock 1994, where they started an infamous mud fight. During the concert, a security guard mistook bassist Mike Dirnt for a stage-invading fan and punched out some of his teeth.
Viewed by millions via pay-per-view television, the Woodstock 1994 performance further aided Green Day's growing publicity and recognition, and helped push its album to eventual diamond status. In 1995, Dookie won the Grammy Award for Best Alternative Album and the band was nominated for 9 MTV Video Music Awards including Video of the Year.


The full fold-out artwork to Insomniac, entitled God Told Me to Skin You Alive.In 1995, a new single for the Angus soundtrack was released, titled "J.A.R.". The single went straight to #1 on the Billboard Modern Rock Tracks chart. The song was followed by its new album, Insomniac, which was released in the fall of 1995. Insomniac was a much darker response by the band, compared to the poppier, more melodic Dookie.Insomniac opened to a warm critical reception, earning 4 out of 5 stars from Rolling Stone Magazine, which said "In punk, the good stuff actually unfolds and gains meaning as you listen without sacrificing any of its electric, haywire immediacy. And Green Day are as good as this stuff gets."]Insomniac used a piece of art by Winston Smith entitled God Told Me to Skin You Alive for its album cover.
The singles released from Insomniac were "Geek Stink Breath", "Brain Stew/Jaded", "Walking Contradiction", and "Stuck With Me". One track, "86", was a reference to the Gilman Street club refusing them entry after the release of Dookie, claiming that they had "gone too commercial."Though the album did not approach the success of Dookie, it still sold seven million copies in the United States of America. Insomniac won the band award nominations for Favorite Artist, Favorite Hard Rock Artist, and Favorite Alternative Artist at the 1996 American Music Awards, and the video for "Walking Contradiction" got the band a Grammy nomination for Best Video, Short Form, in addition to a Best Special Effects nomination at the MTV Video Music Awards.
After that, the band abruptly cancelled a European tour, claiming exhaustion.

In 1987, 14 year old friends Billie Joe Armstrong and Mike Dirnt formed a band called Sweet Children. The first Sweet Children show took place on October 17, 1987, at Rod's Hickory Pit in Vallejo, California where Armstrong's mother was working.
In 1988, Armstrong and Dirnt began working with former Isocracy drummer, John Kiffmeyer (also known as Al Sobrante). Kiffmeyer served as both the bands drummer and business manager, handling the booking of shows and helping the band establish a fan base.

Larry Livermore, owner of Lookout! Records, saw the band play an early show and signed them to his label. In 1989 they recorded their first EP, 1,000 Hours. Before 1,000 Hours was released, the band dropped the name Sweet Children, according to Livermore this was done in order to avoid confusion with another local band Sweet Baby. The band changed their name to Green Day, allegedly due to their fondness of marijuana.

Lookout! would release Green Day's first LP, 39/Smooth in early 1990.
The lyrics sheet of 39/Smooth included a letter purporting to be from I.R.S. Records that claimed the label had made an attempt to sign Green Day. It also included a response from the band making it clear that they were loyal to Lookout! Records, saying that I.R.S. was a "cheesy and washed-up" label.[citation needed] Green Day would record two EPs later that year: Slappy and Sweet Children, the latter of which included some older songs they had recorded for Minneapolis indie label Skene! Records.
In 1991, Lookout! Records released 1,039/Smoothed Out Slappy Hours, a compilation of the 39/Smooth, Slappy, and 1,000 Hours EPs. In late 1990, shortly after the band's first nationwide tour, Sobrante left the East Bay area to attend college.

The Lookouts drummer Tré Cool began filling in as a temporary replacement, and when it became clear that Sobrante did not plan on committing to the band full time, Tré Cool's position as Green Day's drummer became permanent. The band went on tour for most of 1992 and 1993, and played a stretch of shows overseas in Europe. Its second full length album Kerplunk sold about 50,000 copies in the U.S., which was considered quite a large amount for the independent punk scene in 1992

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