Sometimes aperture and depth of field can be a little tricky to get your head around, especially when you’re a new photographer. Matt Granger gives a quick run down of appropriate aperture settings to get the shot you are looking for. Granger mentions the possible aperture settings that will help you with focus as well as where your lens might perform at its best
[Via Matt Granger - YouTube]
I assume most people on this site understand this, but it's definitely a great tutorial/explanation for beginners (and some non-beginners, who knows)
This guy is always funny... that - not the Nikon guy anymore ;)