What is the difference between exceptions that must be handled and those that do not require handling?

In Java, exceptions are divided into checked and unchecked.

• Checked exceptions are exceptions that the compiler requires to be handled or declared in the method signature with throws. They are usually related to external conditions, for example, IOException when working with files.

• Unchecked exceptions are RuntimeException and its subclasses. They do not need to be handled or declared. They usually arise from programming errors, such as NullPointerException or ArrayIndexOutOfBoundsException.

Thus, checked exceptions require explicit handling so that the program can respond correctly to expected errors, while unchecked exceptions are errors that typically indicate bugs and do not require mandatory handling.