Cactus is architectured to consist of modules (we call them thorns) which plug into a core code (we call it the flesh) which contains the APIs and infrastructure to glue the thorns together.

The flesh on it's own doesn't actually do anything. The thorns contain all the real activity, and can usually be divided into application thorns (typically written by scientists, solving problems in physics, astrophysics, engineering, etc) and infrastructure thorns (typically written by computational scientists, providing IO, interpolations, drivers, elliptic solvers etc). We group thorns together into arrangements, depending on their functionality and applicability.

The Cactus Computational Toolkit is a set of arrangements providing general computational infrastructure for many different applications. This page describes the different functionality provided by different thorns in the Computational Toolkit, for details of how to use the Toolkit, see the Documentation links.

Note that all the thorns in the Toolkit can be used for parallel, or single processor, applications.

• Compiling for different architectures