The bugle is one of the simplest brass instruments, normally having no valves or other pitch-altering devices and with all pitch control  achieved by varying the player's embouchure.

Keyed bugles were invented in England in the early 19th century, with a patent for one design, the Royal Kent bugle, taken out in 1811. This bugle was highly popular and widely in use until around 1850.

This variant of the bugle fell out of use with the invention of the valved cornet. Modern instruments classified as bugles are often valved.