Why and how should error handling be used in programming?

Error handling in programming is necessary for the program to respond correctly to unforeseen situations such as incorrect data, network issues, or input-output errors. This increases the reliability and stability of the application, preventing it from crashing.

In Java, error handling is done using try-catch-finally constructs and the exception mechanism. The try block contains code that might cause an error, catch handles specific exceptions, and finally contains code that executes in any case (for example, resource cleanup).

Example:

try {
    int result = 10 / divisor; // may throw ArithmeticException
} catch (ArithmeticException e) {
    System.out.println("Division by zero is not possible");
} finally {
    System.out.println("Operation completed");
}

Thus, error handling helps control the flow of execution and improves user experience.