The image below was my first exposure to masks. I was pretty proud of it the day I did it, but now looking at it, it's like, really? You can do better, haha.
I worked in Photoshop for a living many years ago, but I don't believe I was ever introduced to masks back then. With these lessons I am taking and Youtube, I have learned more about Photoshop and Photoshop Elements in the last month than I did the entire 10 years I designed!