All the widely available indicators are useful for any trader, however you need to know how they are calculated, what are they supposed to indicate and how you can use them, only then you will be able to get what you need out of an indicator, with that being said be careful, there are many people that add 10 indicators or more to their charts making them unreadable, when truth to be told you only need 5 indicators maximum to create a strategy that can make some decent money out of the markets.