Modular

ProcessWire can be seen as a system for executing plugin modules, and nearly everything that ProcessWire does comes from one module or another. This makes it incredibly extensible.

As an entirely modular system, nearly every ProcessWire installation is unique according to what modules are installed. The core installation is composed of about 140 modules, and any number of new modules from the modules directory can be added, or you can easily create your own.

Modules come in many flavors, from common Fieldtype and Inputfield modules (like the ProFields module set) to full admin applications called Process modules, and on to more specific Textformatter, Markup, and countless other types of modules. No matter what need you have, chances are there's a module that covers it. But even if there isn't, building your own modules is surprisingly simple.