[Koha] Time zone and Koha

Hi all, I have my server with Koha running in the US time zone, while my library operates in the Indian timezone. Is there some setting in koha through which I can configure which timezone to use? When I installed koha locally, I found that a timezone file was created under c:/etc (I used the windows installer), but I don't see this file being referenced anywhere in the koha code. Please let me know. Thanks, Venita.