What software do you use to study chess games?

Hello chess enthusiasts!

I'm wondering, what software do people in the chess community most commonly use to study their games? Personally, I use Chessbase and Hiarcs Chess Explorer Pro and like both very similar.

What software do you prefer and why? What are your favorite features of the software? Do you use free or paid programs?

Share your opinions and experiences in the comments. I am curious to see which software is the most popular.

Let's discuss chess software!