Cell
Element of a mesh. Cells are determined by their connectivity. They can have 0,1,2 or 3 dimension.

Component
One integer or real value can correspond to each component of a field and to each entity of a mesh

Descendant connectivity
It is a description of the entities of the mesh with dimension N. This description is made by an ordered list of geometrical entities (nodes, edges, or faces) with dimension N-1.

Edge
An edge of a volumetric or surface mesh. It is composed of 2 or 3 nodes (2 vertex nodes and optionally one middle node).

Entity of a mesh
Geometrical component of the mesh: node, cell, face and edge. Faces and edges are only intermediate entities allowing to define the cells in descendant connectivity.

Equivalence
Equivalence represents a list of correspondance 2 by 2 of the entities of the same dimension.

Face
Face of a volumetrical cell (triangle, quadrangle).

Family
Entities of a mesh are described by a certain number  of characteristics (boundary conditions, groups membership). Families represent classes equivalent to these characteristics (two entities of a mesh can belong to the same family if they have the same characteristics). Every family is determined by a set of attributes and a list of groups membership.

Field
Field consists of one or several scalar components. One definite type is associated to the given field and the values corresponding to different components are all of the same type.

Field profile
Fields can be defined only on one part of the mesh. Profile  of the field or profile of the component of a field indicates which entities of the mesh contain values.

Group
Unordered set of entities of a mesh. One entity can belong to  several groups.

Mesh
Mesh is described by its geometry: list of nodes and list of cells which constitute this mesh. Supplementary information is added with the help of families (initial, boundary conditions).

Nodal connectivity
It is a description of an entity of the mesh by an ordered list of nodes constituting this entity.

Node
Node can be an isolated node of a mesh, a vertex or middle node of an edge. A node is associated to a point.

Point
Geometrical entity determined by its coordinates in the space.

Reference connectivity
For each type of entity of a mesh, reference connectivity define the topology of an entity.

Result
List of fields referring to one mesh.

Study
Study represents a chain of sequences of calculations.