I still remember my first week of engineering school (1997). Before the actual classes started, we had an intensive UNIX week. I loved it. It seemed like the real deal to me. I was already using linux at the time, but for the first time I was properly taught things by experts, and not computer magazines. What was my hobby was suddenly becoming something serious and respected. So much has changed since then but I'm glad that to this day I'm still using the same commands and tools.