The French horn is a brass instrument known for its distinct complicated tubing. Similar to a trumpet, sound is produced when the player buzzes their lips together through the mouthpiece. Pressing down valves and adjusting the pressure of the buzz can change the pitch of the sound. Early versions of the french horn had simple tubing and no valves, often used for hunting. The first valved horn wasn’t invented until the 1800s, but received backlash due to players preferring a “natural”, or valveless horn better. The french horn is most commonly used in orchestras for its middle range among other brass instruments. The most common french horn used by players is the F/B-flat double horn. Read more here: https://en.wikipedia.org/wiki/French_horn