An IPO, or initial public offering, is when a private company sells shares to the public for the first time and lists on NSE or BSE. Investors apply during a window of a few days at a price band set by the company, using the ASBA facility through their bank or a UPI mandate through their broker. Retail applications are in lots; if demand exceeds supply, allotment is by lottery, and many applicants get nothing. Suppose a company offers shares at ₹100 with a lot of 150 shares, so one application blocks ₹15,000. On listing day, the share may open above or below ₹100. Listing gains are never assured; several large IPOs have listed at a discount and stayed there for years. Read the red herring prospectus, look at what the company earns and why it is raising money, and ignore grey market chatter.