MarketXLS functions are custom functions that work exactly like any other Excel function. Start type the function and Excel will suggest similar sounding functions for you to use. Along with inbuilt Excel functions, the new MarketXLS functions will also show up. For example, if you want to use Mutual Funds related functions start typing “=” and MF, for Options starts typing Options. For the Stocks category, there is no prefix. Just start typing what you need.