ZOO is a WPS (Web Processing Service) open source project released under a MIT/X-11 style license . It provides an OGC WPS compliant developer-friendly framework to create and chain WPS Web services. ZOO is made of three parts:
ZOO is based on a 'WPS Service Kernel' which constitutes the ZOO's core system (aka ZOO Kernel). The latter is able to load dynamic libraries and to handle them as on-demand Web services. The ZOO Kernel is written in C language, but supports several common programming languages in order to connect to numerous libraries and above all to simplify the Web service end-developer's job.
A ZOO service is a link composed of a metadata file (.zcfg) and the code for the corresponding implementation. The metadata file describes all the available functions which can be called using a WPS Exec Request, as well as the desired input/output. Services contain the algorithms and functions, and can now be implemented in C/C++, Fortran, Java, Python, PHP and JavaScript.