Computers & IT (Non-Engg)

As the acronyms suggest MCA focuses typically on the application side whereas M.Sc. Focuses on the Science / core concepts. Hence, in general, I would recommend M.Sc. Over MCA. Having said that, there are a lot of factors that one needs to consider before making such a choice as:
Curriculum: Pay attention especially to courses covering core concepts like
Data Structures and Algorithms
Theory of Automata
Operating Systems
Programming Languages
Compilers
Technologies covered: Make sure that you weigh in the coverage of technologies from the current trend like Machine Learning, Virtualization, Python, Docker, DevOps tools like terraform, ansible etc. During the course. Hand on work: The amount of hands on work like labs, projects, practical training, internships are an important aspect to consider. Institutes offering the course: Having all the above factors the same, MCA from institute X might still fare well than M.Sc. From institute Y in some cases. It is based on factors like facilities, faculty, alumni network, joining students of an institute. You need to consider all these factors for deciding between two courses towards your career progression. Some of this analysis applies for any two courses and not just MCA versus M.Sc. Good luck for choosing the right direction for your career!

In Computer Science B.Sc CS.
Bachelor of Computer Application BCA
Bachelor of Technology in Computer Science (B.Tech CS)
If you compare this three on their volume of Course-
BCA B.Sc CS B.Tech CS or BCA B.Tech CS B.Sc CS depending on the college or university. To pursue BCA, you can join from Science, Commerce and Arts background. But, to pursue B.Tech or B.Sc CS, you'll need a solid background of mathematics. The main difference between B.Sc CS and BCA is BCS CS is concept oriented. It will teach you the Core Concept of computer Science, which will help you to learn anything new very quickly, other hand BCA is application oriented, teach current technologies, but learning new technologies or working on Core Computing is difficult. There is a misconception that B.Sc doesn't teach programming language, when I was doing B.Sc. I learned C, C+, Java and PHP and SQL. Also I got a Good Practical knowledge about Electronics and Microprocessor. In B.Sc. I learned about Microprocessors, Automata and Compilers, Data Structure, Analog and Digital Electronics, Networking, Discrete Mathematics, Graph Theory. In BCA they teach the same topics, but a not in a detailed way. B.Sc. CS is a General Course and BCA is a Technical Course, so getting job from BCA is easy than B.Sc. CS. After B.Sc. CS you can do M.Sc. CS or MCA both. But after BCA you can only do MCA. M.Sc. CS You'll get more knowledge in Core Computer Science like Parallel Computing, Artificial Intelligence, Soft Computing, and Information Security. Best of Luck.

If we talk of both technically:
CS takes a more balanced approach between theory and application while IT focuses more on application. CS offers you an opportunity to learn variety of topics related to computers. IT offers you an opportunity to discovers innovative uses of those fundamental concepts. CS generally require a decent background in math while use of math in IT is limited to data analysis / processing / statistics, etc. You may call IT as one of the sub-divisions of CS however there are certain things that are unique to IT like integrated programming, system administrations, maintenance, etc. While these differences exist on paper, in India the line of difference between IT and CS courses is very blurry. Here are the similarities :
None of them involves hardwares. You may have to take one or two courses on digital systems where you will study about ICs and logic gates. That's it. You won't learn how to repair computers in any of them. Most of the courses offered in both the branches are related to programming. You will have to programme on a daily basis in both the branches.