Equity trading or stock trading is the buying and selling of equities in the market through your registered trading account. To understand what is equity trading, you must first understand the concept of equities. Equities are a share of ownership in a company and these shares are traded freely on the NSE and the BSE for listed companies. There are over 4,700 listed equities in the BSE today. You call them by different words like equity, stock, share, etc, but they mean the same thing.