An IPO (Initial Public Offering) is the process by which a private company offers its shares to the public for the first time on a stock exchange, transitioning from private to public ownership. The IPO process involves hiring investment banks as underwriters, filing regulatory documents (like an S-1 form with the SEC in the US), conducting a roadshow to attract institutional investors, and setting an initial price range based on demand. IPOs typically start trading during regular market hours, often opening 30-60 minutes after the market opens as the exchange determines the opening price based on accumulated buy and sell interest. The first day of IPO trading frequently sees high volatility, with some stocks surging 50% or more above their offering price while others fall below it. IPO activity tends to be cyclical, increasing during bull markets when valuations are high and decreasing during bear markets. Major exchanges like NYSE and NASDAQ compete aggressively for high-profile IPO listings.