A favorite is any EA you can use to make money. But EAs don't actually make the money--good traders make money and sometimes use EAs to do it.
You have to find out what kind of trader you are because there are many different ways to approach the market. Start with a demo account and free EAs to see how they work. In Codeshare tab there are a lot of free examples of EAs and indicators based on every approach. You can learn the basics from them and then decide what approach is your favorite.
There are only a few numbers of interest: open, high, low, close, volume .... almost every idea has already been thought of and coded one way or another. You just have to discover the winning code and personal trading style for yourself and then you will have a favorite.
Check out other peoples profiles and just don't believe everything somebody says. One important point for the first months of learning: don't buy a lot of new EAs no matter how cheap until you understand them and test them on demos. There are lots of articles on this site about trading strategies.