How does the average person learn to play Terraria?

Terraria is a great game and I've really enjoyed playing it, but I was only really able to enjoy it after I had someone who knew how to progress through the game play alongside me. If not for him, then I wouldn't know how to progress whatsoever. I still find myself having to constantly search things on the wiki when I play by myself.

How did the average terraria player ever learn how to play the game by themselves??