A secondary market transaction is the buying and selling of securities that have already been issued in the primary market. In other words, it's the trading of securities that are already in the hands of investors, as opposed to being issued by the company for the first time.
The primary market is where securities are first issued, typically by companies raising capital. The secondary market is where securities are subsequently traded among investors. In the primary market, securities are sold directly by the issuer to the investor, while in the secondary market, securities are bought and sold among investors.
The price of securities in the secondary market is determined by supply and demand. If more investors are looking to buy a particular security than sell it, the price will go up. If more investors are looking to sell a security than buy it, the price will go down.
There are risks associated with buying securities in the secondary market, just as with any investment. The value of a security can go up or down, and an investor could lose money. Additionally, there is a risk of fraud when buying securities in the secondary market, which is why it's important to do thorough research and only buy from reputable sources.