Etching is like using your shoes as tiny little crampons, while smearing is more like trying to balance on a slippery surface with just the soles of your feet. A back step is like trying to do the moonwalk on a vertical wall, and a drop knee is like taking that moonwalk to the next level. Heel hooks are for when you need a little extra support, like a heel hook on a pair of high heels. Toe hooking is like trying to balance on your toes, and a foot swap is like trying to play a game of hopscotch on a vertical surface. Index foot matches are when you and your feet are on the same wavelength, and a hand-foot match is like trying to do the splits on a wall. Basically, rock climbing is like a whole lot of fancy footwork.
