Agile and architecture are often considered cats and dogs. Many "classic" software architecture methods are considered an enemy of agile principles: often describing heavyweight, upfront documents and decisions, and a hierarchy with architects wielding all technical decision power and responsibility.
Although there are some new "agile architecture" concepts out there, these typically only address small parts of the problem and often require significant skill to practice correctly. There is even the notion that architecture is not needed anymore when applying agile practices.
But what is "architecture" anyway? This infodeck gives an overview on architecture as a concept, a process and a role. It is delivered as stand-alone slides, and should be useful for anyone involved in building software systems.