Laurence Olivier famously said to Dustin Hoffman on the set of Marathon Man, "My dear boy, why don’t you just try acting?" and that’s pretty much one of the best stories about method acting you’ll hear. It was invented as a useful tool for actors to immerse themselves in a character, which worked well for some, like Robert De Niro, who moonlighted as a cab driver to prepare for his role in Taxi Driver.