checked vs unchecked exceptions

                                    document.getElementById("checkbox_id").checked;
//If checked returns true;
//else returns false;

                                    All subclasses of RuntimeException are called unchecked exceptions. 
These are unchecked exceptions because compiler does not checks if a method 
handles or throws exceptions. Program compiles even if we do not catch the 
exception or throws the exception. If an exception occurs in the program,
program terminates. It is difficult to handle these exceptions
because there may be many places causing exceptions.
Example : 
1) Arithmetic Exception
2) ArrayIndexOutOfBoundsException
3) ClassCastException
4) IndexOutOfBoundException
5) NullPointerException
6) NumberFormatException
7) StringIndexOutOfBounds
8) UnsupportedOperationException

                                    I would either handle or declare. I Declare using THROWS keyword or handle by
using TRY&CATCH block. If I will use it again I would handle it. If it will
occur only once than I would use THROWS keyword

                                    1) Look at the hierarchy, if that exception extends RuntimeException then 
it is an UNCHECKED exception
if that exception extends Exception, Throwable or 
any other Checked Exception, then it is CHECKED exception.
2) Throw it, if it compiles, it is an UNCHECKED exception, 
if not it is a CHECKED exception.
throw new SomeException();

                                    1) Checked Exception is required to be handled by 
compile time while Unchecked Exception doesn't.
2) Checked Exception is direct sub-Class of Exception 
while Unchecked Exception are of RuntimeException.
Checked Exceptions:
No Such Method Exception
Class Not Found Exception
File Not Found Exception
No Such Field Exception

Unchecked exceptions occur at runtime.
No Such Element Exception
Arithmetic Exception
Null Pointer Exception
Array Index Out of Bounds
Exception