ETF (FNB)- An exchange traded fund is a collective investment vehicle or fund in which investors purchase units or shares on the stock exchange and which in turns invests the funds so received. Unless otherwise indicated, it is not actively managed but rather invests across broad markets in similar fashion to a MF-I or index mutual fund. See section Index Funds (ETF’s and Index Mutual Funds) for a discussion. In Europe, ETF's are sometimes referred to as trackers and ETF sector funds as active ETF's; see description Euronext doc.718.