An initial public offering (IPO) is the debut of a private company into public stock markets. IPOs are often issued by smaller, younger companies seeking capital to expand, but they can also be executed by large privately-owned companies or government-owned entities looking to become publicly traded. In an IPO, the issuer obtains the assistance of an underwriting firm, which helps determine what type of security to issue, the best offering price, the amount of shares to be issued and the best timing to bring it to market.