Thinking is the base of all cognitive activities or processes and is unique to human beings. It is a higher mental process through which we manipulate and analyse information received from the environment. For example, while seeing a painting, one goes beyond the visible strokes to interpret meaning and relate it to existing knowledge, creating new understanding.

Thinking is an internal mental process that can be inferred from overt behaviour. For instance, a chess player's strategy can only be inferred from their move. It is also mostly organised and goal-directed. Activities ranging from cooking to solving math problems have specific goals, achieved by planning, recalling past steps, or inferring new strategies.

The process relies on existing knowledge represented as mental images or concepts. Concept formation helps organise knowledge, making the thought process quick and efficient, much like organising books in a library.

Thinking involves complex processes like abstracting, reasoning, imagining, problem solving, judging, and decision-making. These allow for the manipulation of acquired or stored information to solve problems, make inferences, and make decisions.