India is a large country. It covers a long range of longitudes (67°E to 97°E). As we know that variation in time is caused by longitudinal difference, so the time difference between the westernmost and the easternmost longitudes of India should be very large. For example, the time of Arunachal Pradesh should be two hours ahead of Gujarat, but such a situation could cause inconvenience in the activities like transmission of information across different parts of the same country. To avoid this, we designate the 82°30'E longitude as Standard Meridian. The time at this longitude is accepted all across India as the Indian Standard Time.