Chain letter. December 2023. Page Version ID: 1188532303. URL: https://en.wikipedia.org/w/index.php?title=Chain_letter&oldid=1188532303 (visited on 2023-12-08).
This link introduces chain letters, which are messages that ask whoever receive them to pass to others. It talks about how chain letters spread through paper mail before becoming common in email, social media posts, and so on. Some even use scary stories to share them.