The 5 constituencies of consensus in Bitcoin:
1. Software Developers
(making reference implementations)
2. Miners
(implementing run-time consensus for making blocks)
3. Exchanges
(exchanging other currencies for Bitcoin)
4. Wallets
(validate transactions based on consensus rules)
5. Merchants
(exchanging goods for Bitcoin)
From Saylor.org
1:13:00-1:16:00
source: Andreas M. Antonopoulos, https://youtu.be/fw3WkySh_Ho