Your friend really likes you. Sky blue is the color of the sky, and it symbolizes freedom and forever. It's like a big smiley-face for your feet, only less yellow and more blue. Actually, no yellow at all because then the socks would be green because blue and yellow make green, and that would be a good color if it were happy spring green or a quiet, cool forest green and not what-the-hell-did-he-eat cat-barf green, which you don't want on your feet because it would look like you stepped in cat barf (only it would have to be a really big cat to get it on the tops of your feet and up your legs, like maybe a giant radioactive space cat or something). Your friend should give you some pink socks. Nothing that comes out of a cat is pink. At least not unless the cat has a very bad accident. Good thing your friend didn't send brown socks.