When it comes to looking for oil exposure in your portfolio, many investors new to the energy space immediately turn to the biggest names, such as ExxonMobil (NYSE:XOM) and Chevron (NYSE:CVX), to make a safe, stable foray into the energy sector. In the following video, Motley Fool energy analyst Joel South breaks down the numbers and tells investors which of these two giants has performed the best historically and which might be the better play today.