I don't know how much 10 codes were ever used, but since the early 90s, when I started playing around on the CB, there are only a couple ever used. 10-4, 10-20 is kind of used in terms of "What's your 20", and 10-7, although that last one is used very little. As for trucker slang, there is tons of it. "Seat covers", "Bear", "Bear in the air", "City kitty", "County mounty", "Picture taker", "There's a bear takin' pictures", etc. You don't need to know it, and nobody will give you too hard of a time if you don't understand them and ask for clarification. The good thing is, google knows all the slang.