Depending on which publication is conducting the research and who responds to the survey, these might be in any number of combinations on a list of the most popular. Some might not be included in some lists, and others might be at the top in one list and the bottom in another. All of the programming languages in this cluster would be worth the time if you are thinking about learning them. If you are planning on going into a specific career field you should definitely learn about the specific languages that you will need to use for that type of work as well. With the right programming language knowledge, there's no telling where your career can go.