Alright, phillbush and venam covered pretty much all the important parts, but here are some quick notes from me:

Funny how some commands such as ls(1) and cat(1) are just as popular these days, while others are rarely seen eg. mail(1), news(1) and write(1).

Having to use "o" and "oo" while communicating with write(1) is hilarious. What if we still had to do that on irc?

ls(1) used to output just a single column of text, why was that changed?

I had no idea that nohup(1) automatically called nice(1), but that's really smart.

Funny quotes:

Quote:Try ls /usr/games and do whatever comes naturally. Things might be more fun outside of normal working hours.

Quote:The word "linefeed" is a synonym for newline, so this sequence is often called "CRLF," which is nearly pronounceable.