Even if you have a good command of using f-stop numbers and properly exposing photographs, you might not understand the math behind why f-stop numbers are what they are. Here’s a simple (albeit math-filled) explanation by Dylan Bennett of what f-stop is, including a simple trick you can use to memorize the f-stop scale.

Here’s a simple lesson by Dylan Bennett on what depth of field is, how it works, and how to control it in your photography.

If you’re a fan of learning things through Khan Academy, then you might enjoy learning about how ISO works in this similar-styled tutorial by Dylan Bennett. Bennett might not have Salman Khan’s soothing voice, but he does his best to break down the magic of digital camera sensors into easy to understand ideas. For a more detailed and comprehensive understanding of how things work, check out Cambridge in Colour’s excellent tutorials.