> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ntop.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Meshing in nTop

Meshing is the process of dividing a 3D model into thousands of elements to define its shape — the more detailed the mesh, the better the approximation.

There are three main types of meshes: Mesh (also known as a surface mesh), Tet/Volume Mesh (a solid mesh), and FE Mesh (Used for simulation and is a solid mesh). In this lesson, we will focus on this first type, but later in this course, we will also discuss Volume and FE Meshes.

<Frame>
  <img src="https://files.learn.ntop.com/lessons/meshing-in-ntop/102_2_Meshes.jpg" />
</Frame>

Simplified meshes are suitable for manufacturing, while more refined meshes are more suitable for FEA and CFD and can be converted into volume meshes.

* **Surface meshes** use two-dimensional elements — typically triangles or quads — to approximate the outer surface of a 3D body. You can use surface meshes in manufacturing or rendering applications and CAE simulation.
* **Volume meshes**, also known as solid meshes, use three-dimensional elements — typically tetrahedrons, hexahedrons, and polyhedrons — to define the surface and interior structure. To run FE or CFD simulations, you can convert surface meshes into volume meshes.

## **What is a Surface Mesh?**

A mesh/surface mesh is a discretization of a surface geometry using **vertices**, **edges**, and **faces**. **Mesh Connectivity** defines the incidence relations among mesh elements (adjacent vertices and edges of a face, etc.). **Mesh Geometry** specifies the position and other geometric characteristics of each vertex. Other names for a mesh include surface mesh, surface, and domain.