===The Static Mesh===
The Finite Difference technique discretizes the computational domain using a 3D rectangular grid. [[EM.Ferma]] generates a fixed-cell mesh. This means that the extents of the mesh cells along the principal axes are fixed: Δx, Δy, Δz. By default, the mesh cell size is set to one unit project along all the three directions (with Δx = Δy = Δz). To modify the cell size, click the Mesh Settings button of the Simulate Toolbar or right-click on "Static Mesh" in the Navigation Tree, and select "Mesh Settings..." from the contextual menu to open the Mesh Settings Dialog.
{{Note|To obtain accurate results, it is highly recommended to use a square mesh as much as possible.}}