Thinking cap is a colloquial expression used to describe the act of focusing one's mind in a serious and concentrated manner. There are several synonyms that can be used interchangeably with thinking cap, such as brainstorming, mind-wandering, problem-solving, and idea generation. Brainstorming is the process of generating a large quantity of ideas, often done in a group setting. Mind-wandering refers to the process of allowing the mind to wander freely without any judgments. Problem-solving involves finding a solution to a particular problem. Idea generation is the process of developing new and innovative ideas. Regardless of the term used, the important thing is to remain focused, creative and productive.