Learning a musical instrument helps develop your brain, which makes it bigger so you can finally fit into bigger hats. Fill your head with this Groupon.

Choose from Four Options

• $26.40 for two 30-minute private piano or guitar lessons ($70 value)
• $51.60 for four 30-minute private piano or guitar lessons ($140 value)
• $22.40 for two 50-minute group piano lessons ($55 value)
• $39.20 for four 50-minute group piano lessons ($110 value)

Inside a Piano: How Vibrations Create Wagner

Though its notes may last for only half a second, the piano's design is more than 300 years old. Check out Groupon's guide to the instrument's inner workings to learn about the parts you'll be controlling.

Even beyond the black and white of its keys, the piano is filled with contradictions. Its name derives from pianoforte, a hybrid of Italian words meaning "soft" and "loud." Despite the more than 200 strings that produce its sound, symphony orchestras classify the piano as a percussion instrument. Outside, it is large and elegant, its sound swelling through the concert hall. Inside, it is delicate and complicated—the result of almost 9,000 moving parts working in tandem to amplify an almost silent vibration.

When the player presses a piano key, it triggers a tiny wooden hammer covered in felt to spring up and hit a set of tensioned strings made of hard steel wire. These strings then vibrate at a certain frequency, which causes a large, flat wooden board within the piano casing to vibrate at the same frequency, converting the mechanical energy into a full, discernible sound. If the player releases the key, a felt block called a damper presses against the string to absorb the vibration and silence the note before it wakes the audience asleep in the balcony. Each string must be finely tightened to assume the correct frequency, which creates a lot of tension: in modern pianos, the total strings sustain an average of 20 tons of pressure, which requires a massive iron plate bolted to a heavy wooden frame to support.

Despite the simple concept, a piano's mechanism presents several complicated problems. For instance, the hammer must not only retreat from the string immediately, so as not to dampen the vibration, but also refrain from bouncing back and hitting it again. The solutions to the various technical issues came all at once—the result of the ingenuity of Bartolomeo Cristofori, an instrument maker appointed to the Grand Prince of Tuscany's court in 1688. No later than 1700, Cristofori arrived at his concept for an instrument dubbed "arpi cimbalo del piano e' forte." Cristofori's design was so innovative and complex that subsequent inventors failed to find any easier alternative, and eventually the prototype pianoforte became the world standard.