who are its members?
Julian Casablancas, Nick Valensi, Albert Hammond Jr., Nikolai Fraiture, and Fabrizio Moretti.
The Strokes
 singer Julian Casablancas, guitarists Nick Valensi and Albert Hammond Jr., bassist Nikolai Fraiture, and drummer Fabrizio Moretti. 
what is " is this it" ? A debut studio album by American rock band the Strokes
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The Strokes [SEP] Introduction
The Strokes are an American rock band from Manhattan, New York. Formed in 1998, the band is composed of singer Julian Casablancas, guitarists Nick Valensi and Albert Hammond Jr., bassist Nikolai Fraiture, and drummer Fabrizio Moretti. They are one of the more prominent bands of the garage rock and post-punk revivals, aiding in the resurgence of indie rock in New York City. After the release of their EP "The Modern Age" in January 2001, a bidding war ensued among major labels in order to sign the band. Eventually, RCA Records signed them and released their debut studio album, "Is This It", later that year.