Big data fund, as its name implies, is a fund with big data on the Internet as its information source and mining useful information as its main stock selection standard and means. Big data funds first appeared in the form of index funds. As the market's enthusiasm for big data continues to heat up, product forms are becoming more and more diversified, and more and more manual stock selection factors have been added. According to the investment philosophy, these funds can be divided into passive index type and active management type, and the active type can be divided into mixed type, stock type and capital preservation type.