The Liberty Bell was known as the "Old State House Bell" until 1837, when it was adopted by the American Anti-Slavery Society as a symbol of the abolitionist movement.
The bell rang on July 8, 1776, to summon citizens of Philadelphia to the State House for the first public reading of the Declaration of Independence.
The bell was ordered in 1751 by the Pennsylvania Provincial Assembly for use in the Pennsylvania State House (now known as Independence Hall) in Philadelphia. The year 1751 was the fiftieth anniversary of William Penn's Charter of Priviledges, which gave certain rights to citizens of the colony of Pennsylvania.
The names Pass and Stow seen on the bell refer to the owners of the metal shop that recast the bell after the original cracked during its first ringing in 1751.
The large crack that runs down the "front" of the bell was not caused by ringing the bell. It is actually an attempt to repair a crack by drilling out the damaged section of the bell so that the two edges of the crack don't rub together.