Explain what an exception is in programming and how to use it correctly.

An exception is a mechanism for handling errors or unusual situations in a program that allows you to interrupt the normal flow of execution and switch to an error handler.

Proper use of exceptions:

• Use for handling errors that cannot be predicted or checked in advance (e.g., input/output errors).
• Do not use for controlling the normal flow of the program.
• Wrap potentially dangerous code in try-catch blocks to catch and handle exceptions.

Example in Java:

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

Thus, exceptions help make the code more reliable and readable by separating error handling logic from the main logic.