Why we do set the CLASSPATH and PATH in JAVA? Is it must ?

PATH:     Actually The Path variable set in java for locate Exicutable Files. as like JAVAC.EXE,JAVADOC.EXE,JAVA.EXE Or .Bat (batch files)   so on..,.

Ok ..

It is not manditory to set PATH in "Environmental Variable"..
 We Can also set PATH at runtime also..K..like this
 

C:\Program Files\Java\jdk1.6.0\bin\javac MyClass.java

       NOTE: We are locating .EXE files related to compiller.. Ok....


But the advantage of set PATH as Perminant is While we rebooting the System ,then no need to again set
the Path..Ok..


CLASS PATH:      We keep all jar files and class files in classpath variables..
It consist all .JAR files or .CLASS files

C:> set CLASSPATH=