Geography--definetion of IST(Indian Standard Time)?What are the importance of IST?

Could someone please help me to define IST (Indian Standard Time) and the importance of it?

I S T Info.

Use the link below, it has the relevant information u have asked for
http://www.freebase.com/view/en/indian_standard_time

Cheers,
Aashrith.

P.S : There is a wiki link the the above page if u need more info. abt IST.

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