When you give a movie a positive rating or add a movie to your Watchlist, we track that as a movie that you are interested in and then compare your data to ratings made by other IMDb users.
We can then find movies and TV shows that people with similar tastes to you like. For each recommendation, you can see a list of the movies or TV shows upon which the recommendation was based.
You have either rated these titles highly, or added them to your Watchlist.