Unchecked exceptions are subtypes of RuntimeException.
Subtypes of Error are also considered unchecked.
Everything else is checked.
Yes, you need to know this, and what exceptions are which, for the exam.
If you have K&B (or any other decent study book) that will contain a full description of the important excpetions, including which ones are thrown by the JVM and which ones programmatically (you need to know that too).
Have a look at the JAVA API, starting at java.lang.Throwable or java.lang.Exception. This will also help you understand the Exception Hierarchy more also, and differentiate between Checked and unchecked Exceptions.
be a well encapsulated person, don't expose your privates, unless you public void getWife()!