Improvisation is the practice of acting, dancing, singing, playing musical instruments, talking, creating artworks, problem solving, or reacting in the moment and in response to the stimulus of one's immediate environment and inner feelings. This can result in the invention of new thought patterns, new practices, new structures or symbols, and/or new ways to act. This invention cycle occurs most effectively when the practitioner has a thorough intuitive and technical understanding of the necessary skills and concerns within the improvised domain. Improvisation can be thought of as an "on the spot" or "off the cuff" spontaneous activity.
The skills of improvisation can apply to many different abilities or forms of communication and expression across all artistic, scientific, physical, cognitive, academic, and non-academic disciplines. For example, improvisation can make a significant contribution in music, dance, cooking, presenting a speech, sales, personal or romantic relationships, sports, flower arranging, martial arts, psychotherapy, and much more. Techniques of improvisation are widely trained in the entertainment arts; for example, music, theatre and dance. To "extemporize" or "ad lib" is basically the same as improvising. Colloquial terms such as "let's play it by the ear", "take it as it comes", and "make it up as we go along" are all used to describe "improvisation".
The simple act of speaking requires a good deal of improvisation because the mind is addressing its own thought and creating its unrehearsed delivery in words, sounds and gestures, forming unpredictable statements that feed back into the thought process (the performer as listener), creating an enriched process that is not unlike instantaneous composition .
Where the improvisation is intended to solve a problem on a temporary basis, the "proper" solution being unavailable at the time, it may be known as a stop-gap. This particularly applies to engineering improvisations.