India's single UTC+5:30 zone — anchoring 1.4 billion people
India runs on a single timezone (IST, UTC+5:30) across the entire country — one of only a handful of nations covering a large east-west span with just one offset. The 30-minute increment is unusual: it exists because Indian Standard Time was set at the 82.5°E meridian in 1906, splitting the difference between Kolkata (east) and Mumbai (west). India does not observe DST. Business hours run 9:30 AM - 6:30 PM IST typically, with IT / BPO shifts extending later to overlap US working hours.