Depending On The Era And Style, There Are More Pitches
You may have noticed that most electronic tuning devices have the default pitch set at A=440Hz. The same applies to all sorts of electronic music instruments. It merely means that the musical note of A above middle C makes the air vibrate at the frequency of 440 times per minute, and the frequencies of other notes are adjusted accordingly (often using the equal temperament). The result of that default action is that the majority of pop music is performed and recorded at A=440. However, it is a somewhat new development and has not always been like that. This standard was taken up by the International Organization for Standardization only in 1955 as ISO 16 (Wikipedia link). Before that, there were no standards. If you are interested to know why then I recommend you to take 10 minutes to watch Elam Rotem explaining it in the EarlyMusicSources.com Episode about the historical pitch https://youtu.be/si6QNVn40GM
In the early music movement, which mostly involves performing the music that was composed before the 19th century, there are several pitches used. For example, A=392 for the French baroque, A=415 for German high baroque, A=466 for some organ music, and also A=440 for the early Italian baroque. If you are a guitarist and have seen a notice 'tune your instrument a semitone lower' at the top of some tablatures, then this also means that the band has recorded this music at A=415. It is not hard to see that 392, 415, 440, and 466 are all a semitone apart and thus are spots on the same grid, that is defined by the famous A=440. So that particular standard influences even those who try to escape from it.
There are some deviations to mention here. Namely, around the 19th century, the most common pitch seems to have been between A=430 to 435. Most modern pianos and orchestras sound at A=442 to 445.
Finally, one thing is to talk about the tunings, but the live performance situation may be something completely different. I was recently playing the theorbo at a performance of J.S. Bach's St. Matthew Passion, and although it was planned to tune at A=415, the organ started to rise during the performance (3 hrs long piece!) and ended at around A=420. The harpsichord did not change that fast and ended up at around A=417. The other members of the basso continuo group had to tune somewhere in between. What did the choir and soloists do? Who knows. So in real life, different tunings can live together, and you cannot always plan.
The tuner here at the https://tuneit.online website here can help you to tune at whatever pitch you may like.