NSE (National Stock Exchange) which was established in 1992.
BSE (Bombay Stock Exchange) This is a very old stock exchange, it was established in 1875.
When any company is started, it takes a lot of money. The directors of the company cannot invest this money, so they list the company on the stock exchange from where millions of shares are issued.
Companies are listed on the stock exchange from where their shares are bought and sold. But you cannot buy and sell shares directly from the stock exchange.
for this, you will need a broker. In earlier times there were offices of stockbrokers, you had to go there to open the account and you had to tell them in which stock to invest money and sell it.
So you cannot buy and sell shares directly from the stock exchange, rather you have to take the help of a broker and you will have to open a Demat account through the broker.