While there are many people involved in the back-end operations of stock market, the two entities that you should know about are a Depository Participant and SEBI. A depository is a place where the stocks of investors are held in electronic form. The depository has agents who are called depository participants or DPs. You can compare it to a bank where the depository is like the main office with all the details of the accounts and DPs are like the branch offices. In India, there are 2 depositories and over 100 DPs. These DPs act as custodian of your shares. You just open your demat account with these DPs and manage all the money in your share transactions through them.

Another important organization you need to know about it SEBI - it regulates the stock market to protect and safeguard the rights of the investors. You can visit www.sebi.gov.in to get information about SEBI.