Picture and sound compressed, sent and rebuilt many times a second, both ways at once. A weak upload hurts how others see you, not how you see them.
The drawing that proves the sentence above. It is the same card that is in the book.
Think of it as
a window opened between two rooms far apart.
For example
They can see and hear you fine, but say you look frozen. Your picture going out is the small pipe, not the one coming in.
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.