Behaviours are responses or reactions

Behaviours are responses or reactions we make or activities we engage in. When
something is hurled at you, your eyes blink in a simple reflex action. You are taking an examination and can feel your heart pounding.

You decide to go for a particular movie with a friend. Behaviours may be simple or complex, short or enduring.

Some behaviours are overt. They can be outwardly seen or sensed by an observer. Some are internal or covert.

When you are in a difficult situation while playing a game of chess you almost feel your hand muscles twitching, trying to experiment with a move.

All behaviours, covert or overt, are associated with or triggered by some stimulus
in the environment or changes that happen internally. You may see a tiger and run or think that there is a tiger and decide to flee.

Some psychologists study behaviour as an association between stimulus (S) and response
(R). Both stimulus and response can be internal or external.