An IPO is an initial public offering, when a company first sells shares to the public. A Hot Issue is an upcoming IPO that is heavily oversubscribed by the investing public. It is commonly associated with companies in glamorous or high-tech industries.The reason why IPOs are so popular is because they offer investors a chance to get in on the ground floor of a potentially successful company. When a company goes public, it means that its shares are now traded on the stock market and anyone can buy them. This offers investors an opportunity to make a lot of money if the company does well, as their shares will go up in value along with the company's stock price.However, there is also a lot of risk involved in investing in IPOs. Many times, these companies are unproven and may not be successful long-term. Additionally, there can be significant volatility in share prices during the first few months after an IPO as investors try to figure out what the true value of the stock should be.