The FEniCS Project is designed as an umbrella project for a collection of interoperable components. The core components are
A schematic overview of the FEniCS components and their interplay
UFL (Unified Form Language), a domain-specific language embedded in Python for specifying finite element discretizations of differential equations in terms of finite element variational forms;
FIAT (Finite element Automatic Tabulator), a Python module for generation of arbitrary order finite element basis functions on simplices;
FFC (FEniCS Form Compiler), a compiler for finite element variational forms taking UFL code as input and generating UFC output;
UFC (Unified Form-assembly Code), a C++ interface consisting of low-level functions for evaluating and assembling finite element variational forms;
Instant, a Python module for inlining C and C++ code in Python;
DOLFIN, a C++/Python library providing data structures and algorithms for finite element meshes, automated finite element assembly, and numerical linear algebra.
DOLFIN functions as the main problem solving environment and user interface. Its functionality integrates the other FEniCS components and handles communication with external libraries such as PETSc, Trilinos and Eigen for numerical linear algebra, ParMETIS and SCOTCH for mesh partitioning, and MPI and OpenMP for distributed computing.