the first thing i ever truly built was, if i remember correctly, on a server where a house made by A.R.C. was loaded.
another guy on the server showed me inside and taught me how a lamp works.
i had loaded the demo house before and seen the light there flick on and off, and had no idea how to do it, so i was happy to learn. i placed a 1x1 round on the ground and this guy told me step by step how to event it to work and add a little sound every time it was clicked.
it was amazing ;-;