You will find that companies happen to sell a part of their ownership to the public in exchange for money. The investors can buy the company’s shares for the amount they invest in and become shareholders. The shares they own are called equity. These shares can be traded in the stock market, either primary or secondary market. In the primary market, the shareholder can buy new securities as an initial public offering. However, the secondary market offers the option of purchasing and selling securities that have been issued already. A lot of this information can help you get interested in trading if you are aware. More than 1300 securities are currently available on the National Stock exchange and over 6000 on the Bombay Stock exchange for equity trading.