
While its characteristics change over time, the concept of "coolness" remains constant: it's all about the attitude. Being hip requires personality; a bit of badassery will do the trick, and age need not stand in your way. If you're especially trendy, you'll be happening long after the moment is captured on camera, just like these 20th-century celebrities.
Just because they're in black and white doesn't make them any less cool. If anything, it's old school, which anyone will tell you is the best type of cool.
20 Rare Photos of World-Famous Celebrities In The 20th Century,
1960: Muhammad Ali
1930: Buster Keaton
1931: Sigmund Freud
1968: Arnold Schwarzenegger
1972: Debbie Reynolds And Carrie Fisher
1960: Alfred Hitchcock
1955: Walt Disney And Salvador Dali
1938: Judy Garland
1957: JFK
1969: The Beatles