A happening is a particular type of art form. It emerged from performance art and was at its prime during the 1950s and 60s. The term was coined by Allan Kaprow who apparently was responsible for organizing some of these abstract, interactive performances and events.In a happening, there is no purpose, and no control--unlike that of traditional art and authority which contains both a purpose and a degree of control in both the individual artist and the viewer.
Yet a happening is not an individual form of art or occurance. It is collective,a group, social. It is indeterminate, created by whim, chance, or fancy. The happening is impermenence. In other words, it is not static. On the contrary, there is flux, change. If a particular happening (performance) is repeated, chances are that it will never be exactly the same. In a way, it's like improv where anything can happen and does. In addition, happenings are dependent upon context, it matters where it is held, and all depends upon the space it is held within--be it physical, mental, social or political. The Happening is a counter rationality, as it is different to what most humans are use to. For instance, there is no permenece--humans (myself included) generally do not like change. Humans also prefer controland purpose as well as success as oposed to failure--chance--which is basically what the happening is all about. It is about chance or failure, as well as the idea of embracing the idea of failure as a possibility and even as a sort of success. Hence it has the ability to envoke, and provoke fear.
Here is an example of a Happening that occured in 1963.