Difference between stock market fund, income fund and money market fund?

No such thing as a stock market fund (at least in the USA). I think you mean a stock (or equity) mutual fund. They are made up of the common or preferred stocks of many companies and increase in value through increasing share price (capital gains) of each company it holds. Current income (through company's dividends) is only a secondary consideration. An income fund, is one whose primary consideration is current income, via dividends from stocks, interest from bonds, or both. Share price can vary so it is possible to gain value via capital gains. A money market fund keeps its share price at $1.00. Primary consideration is current income. It invest in short term bonds, notes, commercial paper (loans) of 90 days or less. (With bonds, the time period can vary from a week to 50 years).

i don know about income fund but ...stock market fund ....are those fund which are used by companies to meet der long term need like acqusition of n assests n are long term in nature having maturity period of more than a year .... all and monkey market fund are short term in duration having maturity periord upto one year ...and are genrally raised by the companier to meet der working capital requirments ....