When looking at surfboard design and performance as a whole, fins are one of the trickiest variables. Clearly, there’s a lot you can gather from simply looking at board length, width, or general shape. (And color. Didn’t you know red boards surf faster?)
But fin setups are far more complex. A tweaked set up can create a board that rides completely different. Since there’s no way to learn about fin configurations (or lackthereof) that compares with actually riding them, these are some of the basics.