The valved trumpet was invented by Heinrich Stoelzel and Friedrich Bluhmeh. It was the predecessor of the modern trumpet we know today, and is important in the development of the musical trumpet and the use of the trumpet in musical pieces. The valves allowed trumpet players to have more flexibility in each partial of their instrument and in so doing, it helped trumpet players play in different keys than their instrument was built in. The addition of valves to trumpets also kick-started the standardization of the trumpet into the different categories ( C trumpet, Bb trumpet, piccolo trumpet, etc.) that we know today. All the variants of the trumpet (with the exception of the slide trumpet, also referred to as the Bb trombone) are derived from the original valved trumpet.