The service itself is down, not your equipment. Checking the provider's status page first saves an hour of restarting things that were never broken.
The drawing that proves the sentence above. It is the same card that is in the book.
Think of it as
the Closed sign up in the middle of the day.
For example
Nothing loads. You restart the box, the laptop and the phone. It was their service all along, and it came back on its own.
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.