They use combinations of securities to meet their goals. Income funds are structured to provide regular income dividends to their investors. Such securities yield relatively stable current income. They focus on paying dividends as their top priority while de-emphasizing the growth in value of their portfolios. Preservation of capital is a concern.
Income funds are popular with investors who want stable income from their mutual funds.
These funds are made up of the securities that comprise major market indexes. The advantage of index funds is that they are always in line with their market index. Their downside is that they cannot outperform the market. Some funds divide their holdings evenly among the various stocks. Some use dollar weighting so that bigger companies comprise a larger share.