WhatsApp group
WhatsApp's group chat feature. Lift from 100 to 256 to 1024 members over the years. Admins can restrict "only admins can send" for announcement mode. Standard communication medium for entire schools, families, villages in India + LatAm.
WhatsApp Communities (2022): hierarchical groups (community → 50 sub-groups), 5000 members. Distinct from Telegram groups: WhatsApp groups are E2EE-default (since 2016 via Signal Protocol). Group disinformation spread classic issue (India's 2019 elections), WhatsApp limited forwarded messages to 5 groups 2019 → large effects on viral content. Classic anti-pattern: 200-person family group with constant "Good morning" emoji spam.