I have heard a lot about this northern part of India, but no idea about this type of investment please share your views about this type of investment.
Chit funds started as group of people pooling money every month and drawing a lot to determine who would get the entire funds that month. For example 5 people pool together Rs 1000/- on first month person "A" gets the draw and takes the Rs 5000/-. Next month again same set of people pool Rs 1000/-, the person who got the money last month is removed from the list and again a draw is made. Thus everyone pays Rs 1000/- for 5 month and gets back Rs 5000/- some sooner and some later. This was done more to buy big ticket purchases, or group of ladies getting together. There is always a leader who would ensure that everyone pays and manages the process.
In more business oriented chit fund, unknown people come together and contribute Rs 1000/-. There is a organiser who is a local strong man who runs this and ensures that everyone pays. The variation here is that every month instead of a lucky draw, you can buy for discount. Say this month you need the money badly, you are willing to take only Rs 4800/-, there maybe some one who is more desperate and may say he is OK with only Rs 4600/-. The balance Rs 400 is distributed amongst the other 4 members. Thus the other who had contributed Rs 5000/- over 5 months now get Rs 100 more. The next month this person is eliminated from bidding, and others 4 can bid for Rs 5000 or less. The balance is again re-distributed amongst others. This is typically run by people who do not get loans at good rates from bank and essentially borrow outside the financial industry. The people who are part of this most of the times make good returns / better than banks. But this entire industry is unregulated and hence the Strong man can dupe you, there are cases where people who take the first shot at money vanish without trace.
Every city has quite a few of such funds running. It is advisable you do not indulge in such funds.