Learning Scripting (VBScript, JavaScript)

u can go to www.w3schools.com
there u can get basics of javascript

Generally with all server side scriptings like php,jsp our request is going to server and come back with response...For some point of views there no need to go to server,like in the example situation validations...So we are going to use client side scripting which dont waste the time....

Now the java script is become more powerful because one most technology is came with the concept of javascript ...that is ajax....by this we can communicate with the webserver with reloading the whole page...In ajax this is done by javascript...

Thanks alot guys. However I still need some examples on what scripting can be used to achieve.

For that you have to search by googleeeeeeeeee.......lots of scripts are there to implement ..
Some sites :
http://dynamicdrive.com/
http://hotscripts.com/