The Indian Standard Time (IST) is based on the 82° E meridian. This means that the standard time in India is set according to the longitude that passes through the point marked at the 82° E meridian.

The meridian is an imaginary line on the Earth`s surface that runs from the North Pole to the South Pole and helps establish the different time zones around the world. Each meridian represents a different longitude value, which helps determine the local time in a particular region.

In the case of India, the 82° E meridian is used as the reference point for setting the standard time. This means that all clocks and watches in India are set based on this meridian, which helps ensure uniform timekeeping throughout the country.

It`s important to note that the 82° E meridian is specific to India and its neighboring countries. Other countries have their own reference meridians for establishing their standard time.