Brass instruments include Trumpet, Horn, Trombone, Baritone (A.K.A. Euphonium), and Tuba (in order from highest pitch to lowest pitch).
All these instruments are played using a metal mouthpiece. You buzz into the mouthpiece by buzzing your lips (putting them together and blowing to create a 'buzz'). For all instruments, make sure you DO NOT puff your cheeks.
These instruments also use valves (either piston or rotary). Trombones are unique as they use a slide to change notes. Each instrument requires valve oil (slide oil for trombone) to be applied daily, and tuning slide grease to be cleaned off and reapplied monthly for general maintenance (see here).
Click on each of the instrument names to see more in-depth and specific information on each instrument!