A real-time water surface simulation renders an animated 3D plane in WebGL. Three.js constructs the scene, geometry, and shader material, while GLSL vertex and fragment shaders compute wave displacement based on time, amplitude, and speed uniforms. The animation loop increments the time uniform each frame, continuously deforming the grid to mimic rippling water. The code imports from Three.js and gl-matrix for matrix and vector math, with the rendering handled by the WebGLRenderer.