Big Beat describes a the style of music performed by Fat Boy Slim, The Chemical Brothers, the Propellerheads and others (most notably on the Skint and Wall Of Sound record labels).
It is named after an event known as The Big Beat Boutique which has been held in many clubs in and around Brighton, UK, where the style of music developed away from the influences of large clubs in London's West End The club itself was named after the music they played, which (unsurprisingly) has Big Beats, aka heavy bass and drum loops.