The earliest trumpets were made of animal horns, hollowed out wood or bamboo shoots, and objects like conch shells. Later metal models were long, straight tubes, which gave way to the coiled, elongated loop trumpet about 1500 and remained the standard in orchestras until around 1800. The trumpet like the one we know today first appeared in 1820, when valves were added. The valves lowered the basic pitch of the trumpet and offered a harmonic series different than older models.
The cornet developed in the 1850s when valves were instituted on the small, circular-coiled post horn. Though used in orchestras during the 1800s, cornets are mainly played in brass bands today. Trumpets and cornets are very similar in both sound and playing technique.
Trumpet players like Miles Davis and Louis Armstrong (who played cornet, as well) are credited with changing the face of popular music with their stunning solos and arrangements.