I keep seeing ads and websites for people who trade foreign currencies in the foreign exchange markets.

I also have heard that this is how George Soros made some of his money along with a few other big investors.

Has anyone invested in the foreign exchange markets before?

What are the main positive and negative aspects?

Is there higher taxes or fees compared to trading stocks?

Do currencies rise and fall based on a certain set of factors that can be tracked or is it largely due to political and economic events that are hard to predict?

Any help would be appreciated as I make a decision about getting involved in the foreign exchange markets.