Understanding Time Signature: How do I identify the time signature of a song?
I have played music for years and I still don't understand what a time signature actually signifies. I understand it from a superficial sense. If given sheet music I could tell you what time signature it is written in. But why is written in that time signature and what impact does it have on the music? Why would something be written in 3/4 and not 3/8? Or for that matter, why not something completely different like 7/8 and add rests to the end. Nor can I figure out how any of this impacts how the music sounds. I feel it is purely notation, yet, some time signatures are common in some genres of music. Furthermore, I have heard multiple people use the phrase that a piece is "played in so or so time signature". How do they know that from just listening to the piece? I am interested in composition and am revisiting the fundamentals. This is something that I have been stuck on and unable to find online.