The concept of an "action figure" was introduced in 1964, when G.I. Joe hit the market. Hasbro, the creators of G.I. Joe, saw the enormous success of Barbie, the 12-inch fashion doll launched by Mattel in 1959, and decided to create a toy with a similar play pattern for boys.
The term "vintage action figure" therefore covers all figures manufactured between 1964-2000 generally. Anything produced after 2000 is generally termed as a "modern" figure or collectible.