Palak Paneer vs Saag Paneer
I go to a local Indian restaurant several times a year. I usually go to the lunch buffet because I love to try and sample as many different dishes as I can. One of my favorite dishes is Palak Paneer ( spinach with Paneer cheese). Any time it is on the Buffet I take a scoop. On occasion there will be Saag Paneer which basically looks and tastes the same. I go infrequently enough that I dont really read what it is, I just look and take, not paying much attention to whether it is Saag or Palak Paneer. Then one day, I decided to look up what the difference is. Palak translates to spinach and Saag translates to greens. When I researched a little more, the greens can be Mustard, turnip, kale, spinach ... greens.
My question is, if not spinach, what would be the most common authentic green that an Indian would use to prepare this dish? Or does it just not matter ?