plop is a conference about pattern languages, aka design patterns, a software engineering technique for codifying design decisions. Briefly, the aim is to illustrate a solution to a problem within a context with notes about rejected solutions and the rationale for rejection. Then if the problem or the context change, the solution can be reappraised; if the problem arises in a different context the solutions can be looked to for reuse.

Generally seen as an extension of object-oriented programming, they have also been used with functional languages and other programming styles.

Generative pattern languages were pioneered by Christopher Alexander in the field of architecture and first ported to software engineering by the Gang of four in their book Design Patterns.

The PLoP home page is at: http://st-www.cs.uiuc.edu/~plop/.