Question

define Indian standard time IST

Answer 1

Indian Standard Time (IST) is the time observed throughout India, with a time offset of UTC+05:30. India does not observe daylight saving time (DSTu) or other seasonal adjustments. In military and aviation time IST is designated E* ("Echo-Star").[1]

Indian Standard Time is calculated on the basis of 82.30' E longitude, in Mirzapur, Uttar Pradesh, which is nearly on the corresponding longitude reference line.[2]