Artificial intelligence (AI) has been a major driver of stock market gains in recent years, and that's likely to continue since we're still in the early stages of this growth story. Analysts predict the AI market will reach into the trillions of dollars -- that will happen in about a decade, illustrating that this is indeed an area with much growth to come. Why you should buy ETFs First, though, let's consider why it's a great idea to opt for an exchange-traded fund (ETF) rather than just picking a couple o ...