Trombone
Made of brass
Was introduced into the modern orchestra in Beethoven's 5th Symphony!
The alto, tenor and bass trombone are the most common
Has a slide instead of valves and may additionally have one or two valves to lower the sound of the instrument by 5 notes
The slide is made of a small tube inside a larger one. There are 7 places along the slide to get the different notes
Uses a mute to change the sound colour