Funds that specialize within a certain industry are often called sector funds. These are quite risky as they have not diversified away the industry specific risks. Yet another way of classifying funds is where the assets are located. For example you can have Domestic or International funds. One important reason for locational municipal bond funds is for tax purposes.
Interest earned on municipal bonds is tax-free in the state of the municipality.
Thus an investor in Nebraska that buys a muni-bond issued by the Omaha City government need not pay state or federal tax on the interest. The interest on the bond would however be taxable for an investor in New York. Funds that take very large bets on various types of investments. Very low liquidity. Money is generally tied up for at least a year.