What is the genre of books in which you make choices within the book and have different storylines each time?!?

Ok, so my friend once had this book where when you open the first page, you have 2 options to choose from (for example, deciding whether you are going to college after high school or on a road trip), and each decision has a corresponding page to turn to next. The result is completely different stories each time. I just wanted to know if anyone knows what these books are called, because my friend doesn't remember the name of the book, and I really want to go find it because it was so fun!! If anyone knows the genre of books like this that would be so helpful. I've already tried "Adventure" and "Turn-Page Adventure" books, and it feels like the name is on the tip of my tongue. HELP!!!!