Some people still ignore what an ETS is. Simply put, it is the acronym for Extended-Traded Fund and it trades commission free. According to one of the last Morningstar tallies, there are 648 different strategies. This impressing number is the reason why it is very difficult to define every strategy and to find the right approach to each and every one. Some of them are very similar to others and have the same tactical core name but this doesn't mean they are similar in terms of investment. ETS is a good way to invest but you must know the mechanism very well to avoid losing money.