why should we program for exceptions java code example

Example 1: exceptions you get in java

Unchecked:
-IndexOutOfBounds exception(while working with arrays/strings)
-NullPointerException(if I forget to instantiate the objects)
-ArithmaticException

Checked:
-IOException
-SQLException
-FileNotFountException

Example 2: how do you handle exceptions in java

I use try & catch blocks to handle any exceptions in my code. 
  I am familiar with major checked and unchecked exceptions and 
  handle it accordingly to make my code execution smooth