Piano music is usually written using something called The Grand Staff…
The Grand Staff is a set of concise and elegant symbols, a unique symbolic language, that communicates an incredible amount of information in a very economical way.

Such information may include any or all of the following…
- The key center and tonality (key signature).
- Any changes of key or tonality.
- The meter. (time signature)
- Which notes to play, when to play them, how long to play them, and in what manner to play them.
- When not to play (rests).
- Phrasing
- Repeats
- Pauses
- Tempo (how many beats per minutes)
- Acceleration or Deceleration of Tempo
- Dynamics (loud, soft, changes in loudness)
- Fingering
- Can you think of some others?