To put it simply, "key" is the position of the pitch, that is, the height of the note. To be more precise, it is the pitch position of the "main tone".

When we listen to concerts, we often listen to the Sonata in E flat minor and the Piano Concerto in D major. This "E flat minor" and "D major" means that this work is in E flat or If D is the main vocal, it can also be written like this. 1=be

1=D

In any work, every note can become the main note. In total, there are 12 key names and 17 key names. (This is due to the relationship between equal notes, such as pitch, (#5=ba

#c=bd). These key names are: C key, C sharp key (bd key), D key, D sharp key (be key), E key, F key, #F key (bG key), G key, #G key (bA key), A key, #A key (bB key), B key

In addition, "key" also includes mode and tonality, for example, a piece of music. There will be a "transposition" when playing a section, and there may be two situations. One situation may be a change of mode, and the other may be a change of pitch.

Note: In addition. We often see "tune" appearing in the names of folk music, such as "Zizhu Tune", "Long Tune", "Minor Tune", "Huadeng Tune", "Mountain Tune" and so on. It does not mean tonality. There are also some "arias" and "recitatives" in operas, which mostly refer to the "tune" in the above two situations. , has nothing to do with the tone we are talking about.