What kind of music do you play on piano? Jazz? Blues? Rock? Pop? Classical? Whatever style you're into, you'll learn a LOT by going back to the beginning and working your way through each era up to the present.
By "beginning," I mean the very beginning.
If you play jazz, this means to blues, ragtime, spirituals, Latin dances, and marches that influenced early jazz. You'll eventually re-encounter these musical elements in everything from Ellington to bebop (Charlie Parker's "The Hymn") to Chick Corea's "Armando's Rhumba."
For classical, this means going back to Gregorian chant and perhaps earlier. You'll certainly listen to everything from Bach to Stravinsky differently after you do that.
If you love pop, check out some of the wonderful country music from the 1930's. You'll hear these influences surface in everything from Taylor Swift to Bruno Mars ("Count On Me"). And you just might fall in love with some of the classics in what's now called The Great American Songbook. (Check out "Skylark" for starters).
I'm always doing this myself, and it's enriched my musical experience more than I can convey in words. Here's a video of me playing 17 styles of blues piano, in roughly chronological order. I had a lot of fun making this and I hope it inspires you to learn as much about your favorite kind of music as you possibly can. You'll find it's well worth the effort!
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