how include terrain in cesium?

How can I using terrain?
Terrain setting should apply on *.html or cesium.js? your doucument is not clear. please help me more.

See the Terrain example in Sandcastle for a working code that enables terrain in Cesium:


I saw. But I dont know, where should I add this code? Please help me. I want to add terrain for cesium viewer. please help me and tell what should I do step by step.

The code at the bottom of the example Kevin pointed you to is responsible for adding the terrain. Add the code in whatever file you’re creating the cesium viewer in.

var scene = viewer.scene;

var centralBody = scene.getPrimitives().getCentralBody();

centralBody.depthTestAgainstTerrain = true;

var terrainProvider = … /* whatever terrain provider you want to use*/

centralBody.terrainProvider = terrainProvider;