Robert Frederick Zenon Geldof KBE (born 5 October 1951) is an Irish singer-songwriter and political activist. He rose to prominence in the late 1970s as lead singer of the Irish rock band the Boomtown Rats, who achieved popularity as part of the punk rock movement. The band had UK number one hits with his co-compositions "Rat Trap" and "I Don't Like Mondays". Geldof starred as Pink in Pink Floyd's 1982 film Pink Floyd – The Wall. As a fundraiser, Geldof organised the charity supergroup Band Aid and the concerts Live Aid and Live 8, and co-wrote "Do They Know It's Christmas?", one of the best-selling singles to date.

Geldof is widely recognised for his activism, especially his anti-poverty efforts concerning Africa. In 1984, he and Midge Ure founded the charity supergroup Band Aid to raise money for famine relief in Ethiopia. They went on to organise the charity super-concert Live Aid the following year and the Live 8 concerts in 2005. Geldof currently serves as an adviser to the ONE Campaign, co-founded by fellow Irish rock singer and activist Bono, and is a member of the Africa Progress Panel (APP), a group of ten distinguished individuals who advocate at the highest levels for equitable and sustainable development in Africa. A single father, Geldof has also been outspoken for the fathers' rights movement.