There are 4 Types of 2D Animation. Frame-by-Frame, Rotoscoping, Cut Out Animation and Rigged Characters with Inverse Kinematics. To know what type of Animation is best for your project, depends on what you need. Each one has its own Pros and cons. With some you can achieve anything you want, your imagination is the limit, but you have to invest hours and even days to achieve very little. While others can be very fast and easy process, but have many limitations on what you can achieve.