Time in India
This time is showing on the basis of UTC+05:30
The Republic of India uses one time zone, which is Indian Standard Time (IST). This is UTC+05:30 — that is, five and a half hours ahead of Coordinated Universal Time. India does not observe daylight saving time (DST or summer time).
The official time signal is given by the Time and Frequency Standards Laboratory. The IANA time zone database contains only one zone, namely Asia/Kolkata. The date and time notation in India shows some specialties.
Some older time zones were:
During the Sino–Indian War of 1962 and the Indo–Pakistani Wars of 1965 and 1971, daylight saving was briefly used to reduce civilian energy consumption.
One of the earliest known descriptions of standard time in India appeared in the 4th century CE astronomical treatise Surya Siddhanta. Postulating a spherical earth, the book described the thousands years old customs of the prime meridian, or zero longitude, as passing through Avanti, the ancient name for the historic city of Ujjain (23°10′58″N 75°46′38″E / 23.18278°N 75.77722°E), and Rohitaka, the ancient name for Rohtak (28°54′N 76°38′E / 28.900°N 76.633°E), a city near the Kurukshetra.
...
Wikipedia