Automation is the downgrading of a controlled action to an automatic process.

Consider, for example, the changes that occur while learning to type. At first, effort and attention are devoted to the smaller movement or minor decision, and performance is slow and error-prone. After extensive training, long sequences of movements or cognitive processes are carried out with little attention′
Controlled processing is characterized as a slow, generally serial, effortful, capacity-limited, subject-controlled processing mode that must be used to deal with novel or inconsistent information ′
Automatic processing is a fast, parallel, fairly effortless process that is not limited by short-term memory capacity, is not under direct subject control, and performs well-developed skilled behavior ′ (Schneider 1985:475f apud Givón 1989:250)