Real question - not sure if you guys are serious? It’s my least used service these days due to the quality and longevity of its content (outside of the kids shows)
This means that if you log in and get keylogged/shoulder surfed etc they don’t get the full pin. The next time you login you will get asked for different characters.
This seems somehow worse than simply requiring the same few characters each time, since they would either have to store the complete passwords in plaintext, or compute and store the hash for every permutation of 2-3 characters, which is wildly inefficient. You’d also be susceptible to leaking your password if for some reason you are under long term surveillance, since at some point you would presumably have provided all of the characters making up the password.
Just in case you’re not joking - the blue bubbles in the iOS Messages app denote that the text was sent via iMessage, vs SMS which show up in green.
iMessages typically send over WiFi rather than cellular (but can do both) and offer extended functionality like read receipts, Tapback replies (think like a thumbs up or laugh), integration with FaceTime, Freeform, and other iOS features.
You tend to notice when people aren’t using iMessage around the holidays when mass texts to Android/iOS users include things like, “weariedfae laughed at lando55 laughed at joedonuts surprised at alansmithee’s message.”