Draped Bust
This quarter was designed by Robert Scot and was minted from 1796 to 1807. It featured Lady Liberty and the word "Liberty" on the front and an eagle on the back. All of the mintage was coined in Philadelphia.
Capped Bust
This design from John Reich was minted in Philadelphia from 1815 to 1838. The front featured a more heavyset Lady Liberty and had "25 C." on the reverse under the eagle, unlike the draped bust quarter that had no amount listed on it.
Seated Liberty
This popular design by Christian Gobrecht featured a seated Lady Liberty holding an American flag on the front and an eagle on the reverse with olive branches and arrows in its talons. This same design was also used for the half dollar and dollar coins for many of the same years that the seated Liberty quarter was minted (1838-1891). These quarters were minted in Philadelphia, New Orleans, San Francisco and Carson City, Nevada.
Barber or Liberty Head
This quarter is often called the Barber for its designer, Charles E. Barber. It features a male Liberty on the front with an olive leaf headband and the eagle on the reverse. It was minted in Philadelphia, Denver, New Orleans and San Francisco from 1892 to 1916. The same design was also used on the half dollar during the same time period.
Standing Liberty
This design by Hermon A. MacNeil features a female Liberty holding a shield in her left hand and an olive branch in her right. The reverse features a flying eagle with wings spread. This coin is hard to find in mint condition because the features wore off very easily. This quarter was minted from 1916 to 1930 in Philadelphia, Denver and San Francisco before giving way to the Washington quarter in 1932.