If you grew up in the south, the range of the eastern coral snake, at some point you heard the thankfully easy to remember rhyme:

Red touch yellow
Kill a fellow
Red touch black
Friend of Jack

The poem refers to the color of two very similar looking but oh so different snakes. The eastern coral snake has bands of red, yellow, and black but the red bands are always next to the yellow. The kingsnake has the same color bands but red bands always touch black. Good to remember because the coral snake has the most potent venom of any American snake while the kingsnake is harmless (except to other snakes).

Photo by FWC Fish and Wildlife Research Institute