Brainstorming is an organized approach for producing ideas by thinking without interruption. The term was coined by Alex Osborn.
Brainstorming can be done either individually or in a group; in group brainstorming sessions, the participants are encouraged, and often expected, to share their ideas with one another as soon as they are generated. The key to brainstorming is not to interrupt the thought process. As ideas come to the mind, they are captured and stimulate the development of better ideas. Brainstorming is used for enhancing creativity in order to generate a broad selection of ideas in leading to a unique and improved concept.
In a group, it is often emphasized in brainstorming sessions that you should put criticism 'on hold'. Instead of immediately stating what might be wrong with an idea, the participants focus on extending or adding to it, reserving criticism for a later 'critical stage' of the process. The assertion is that when suspending judgment, you create a supportive atmosphere where participants feel free to generate unusual ideas. However, persistent respectful criticism of ideas by a minority dissenter can reduce groupthink, leading to more and better quality ideas.