Household things given a chip and a connection. Most depend on the maker's servers, so a company closing down can quietly turn a working device into an ornament.
The drawing that proves the sentence above. It is the same card that is in the book.
Think of it as
a house with a nervous system.
For example
The lights come on at dusk without anybody touching a switch. Then the company that made them closes down, and they are just lamps again.
This is one card out of 275.
The hundred words you meet most are free — the whole set, animated, in one file that works with no internet.
Volume 1 has all 275 in fifteen chapters, with Staying Safe the largest chapter on purpose.