Adopted from the following great insight shared by Charles Duhigg from the book The Power of Habit

Habits develop in a region of limbic brain named “basal ganglia”.

The habit loop consists of three components.

1)Cue – The trigger based on which brain decides whether to consider sequence of actions as habits.

2)Routine – Repetitive sequence of mental , emotional , physical activities that form a repetitive routine.

3)Reward – The reward that is expected out of automating the loop whether good or bad .

It is the ability of the brain to continuously automate repetitive patterns as habits to reduce size of brain and increase efficiency of the brain.

This is an awesome book to understand how to develop good habits & update wrong habits with nicer habits..