System 1 and 2, and HOT and COLD processes refer to the dual-process theory of behaviour (Thaler RH, and Sunstein CR (2009) Nudge.
Mae System 1 a 2 a phrosesau POETH ac OER yn cyfeirio at ddamcaniaeth proses ddeuol ymddygiad (Thaler RH, and Sunstein CR (2009) Nudge.