Chance is the random and unintended potentialities that are in everything and happening all the time in complex events.
Chance can also be deliberately manufactured via deliberate processes.
Change processes often produce novel possibilities that can be harnessed for creative ends. Because chance leads to unintended outcomes it is a powerful source of novelty that is harnessed by evolution and intentional creative processes. The deliberate use of chance is a wonderful method to remove classical forms of authorship and intentionality that can often limit possibilities. Chance as a technique is something that has been well developed by artists and designers as part of algorithmic techniques. The work of John Cage, and the Olipo movement are important examples (see bibliography).
See: exaptation, blocking