Which of Led Zeppelin's four band members was the lead singer?

Robert Anthony Plant CBE is an English singer and songwriter, best known as the lead singer and lyricist of the English rock band Led Zeppelin for all of its existence from 1968 up until 1980, when the band broke up following the death of John Bonham, the band's drummer.

Plant enjoyed great success with Led Zeppelin from the late 1960s to the end of the 1970s. He developed a compelling image as the charismatic rock-and-roll front man, similar to those of contemporaries such as Mick Jagger of the Rolling Stones, Roger Daltrey of the Who, Jim Morrison of the Doors, and Freddie Mercury of Queen. With his mane of long blonde curly hair and powerful, bare-chested appearance, Plant helped to create the "god of rock and roll" or "rock god" archetype. Although Led Zeppelin dissolved in 1980, Plant has occasionally collaborated with Jimmy Page on various projects in later years, including Page and Plant, and the short-lived supergroup The Honeydrippers (with Jeff Beck).