Let's say I'm on live TV and I'm on the movie category and let's say I'm on HBO and I find a movie that I like. But then I'm scrolling down the menu for movies and then I find another movie in Cinemax category. But then I want to go to the previous channel that I had the movie which was HBO. How do I go back to that instead of going through all the channels scrolling all the way up and all the way down to that channel I could just push the button which would be previous channel simple as that..…