Knowing About validation Server side vs Client Side

 Hi, Forum  Members
I am working on asp .net having
frame work 2.0 i used java script validation but some of my friends
using server side  validation  by knowing from text book
client side validation makes better performance than Server side but in
asp .net there is form ='Run At Server 'Attribute which means what i
have writeAny thing  in asp.net form that will execute at Server
then the validation i have wite in java script will they execute at
Server it makes me confuse So if Any Body have Idea on This Validation
Then Write to me Which is Better For me Server Side Validation Or
Client Side which i will Prefer..


Thank You
Subhakanta 
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