ELSS is the term used in the context of equity markets, full form of ELSS is equity linked saving scheme. These are mutual funds which invest into equity markets, they typically have lock in period of 3 years and therefore people who have long term vision should invest in these schemes as one cannot withdraw his or her funds before 3 years. They are similar to other normal stock mutual funds the difference being that they are tax saving and that is the reason why it is quite popular among investors.