AGILE MANIFESTO – a 2001 statement issued jointly by a group of 17 representatives of various development methodologies at the Snowbird Lodge in Utah outlining shared beliefs and principles for a new, more nimble way to develop software. The entire Agile Manifesto is posted elsewhere on this blog.

EXTREME PROGRAMMING (XP) – this pre-dates the 2001 Agile Manifesto by 5 years or so, but is considered a more engineering-driven form of Agile development with an emphasis on 2-person teams, rigid testing protocols, and always-deployable coding status. Not to be confused with coding whatever the hell you want in whatever the hell priority you want. Although sometimes the mistake is understandable.

CRYSTAL CLEAR METHODOLOGY – an Agile methodology fit for small development teams, generally 10 people or less. It focuses on identifying and working on what is most important, and paring down process. It is generally less programmer-centric than XP. It is best described by its founder, Alistair Cockburn, in his book Crystal Clear – a Human-Powered Methodology for Small Teams. Human interaction is considered the most important thing in this methodology. Documentation and artifacts, not so much. There is no truth to rumor that the name crystal clear came from the fact that when you held up the documentation to the light, you could see through it. Well, maybe a small kernel.