Type casting is the process of converting a variable from one data type to another in programming. This is often necessary when you want to perform operations that require specific data types, such as adding an integer to a floating-point number. By casting, you ensure that the data is in the correct format for the operation, which helps prevent errors and improves code functionality. There are two main types of type casting: implicit casting and explicit casting. Implicit casting occurs automatically when the compiler converts a smaller data type to a larger one, while explicit casting requires the programmer to specify the conversion. Understanding type casting is essential for effective programming in languages like Java, C++, and Python.