Pick shapes started with guitarists filing down bone, shell, wood, cuttlebone, metal, amber, stone or ivory to get the desired shape. Most of today's classic guitar pick shapes were created by the company that made the first plastic pick in 1922, D'Andrea Picks. The plastic pick was an idea that Luigi, and his young son Tony, Sr., had after purchasing a few sheets of the tortoise shell-like celluloid from a street vendor. It appeared very similar to the real tortoise shell picks the guitarists used in their Greenwich Village neighborhood.
Most users of picks are familiar with the most popular shape, the 351, which is merely the rounding off of the top of heart, which was a popular pick shape early on. The rounded triangle is the 346 and the small jazz pick, the 358. All these numbers represent the numbers the Luigi & Tony D'Andrea assigned to each of their new "creations" at the request of the guitarists they serviced. Soon after, they requested their names be imprinted on them. D'Andrea Picks was the first company to create custom pick imprinting in 1938, allowing customers to order imprinting up to 12 block letters. One of the first to make the player imprint popular was guitarist Nick Lucas in the early 1930s.

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