The Rat Pack dominated the '50s and '60s as the epitome of Hollywood cool, while Taylor Swift's A-list pals gave the world the term '#squadgoals'. Getty Images, AFP
The Rat Pack dominated the '50s and '60s as the epitome of Hollywood cool, while Taylor Swift's A-list pals gave the world the term '#squadgoals'. Getty Images, AFP

From Frank Sinatra’s Rat Pack to Taylor Swift’s Squad: the coolest members-only clubs in Hollywood