Need help to understand code!

I found this code and when i run it, the code creates particles in a 1024 by 1024 by 128 radius (Like minecraft but particles). I tried anylizing this it, but when i got about half way through i got stuck. I tried looking it up but didn;t fined anything that has a good explination of how it works. Could someone please explain what the code means that i'm confused on. If you could brake it down into what each part does would be awesome. thanks. Code: using UnityEngine; public class NoiseTest : MonoBehaviour{ private ParticleEmitter m_ParticleEmitter; // Use this for initialization private void Start() { m_ParticleEmitter = gameObject.GetComponent<ParticleEmitter>(); } private bool m_FirstTime = true; // Update is called once per frame private void Update() { Debug.Log(m_ParticleEmitter.particleCount); //number of particles in the current particel int count = 0; Particle[] particles = m_ParticleEmitter.particles; for (int x = 0; x < 1024; x++) { for (int z = 0; z < 1024; z++) { for (int y = 0; y < 128; y++) { float groundHeight = PerlinSimplexNoise.noise(x*0.001f, z*0.001f, y*0.001f)*64.0f; groundHeight += PerlinSimplexNoise.noise(x*0.01f, z*0.01f, y*0.01f)*32.0f; groundHeight += PerlinSimplexNoise.noise(x*0.1f, z*0.1f, y*0.1f)*4.0f; //groundHeight = Mathf.Clamp(groundHeight, 0, 127); particles[count].position = new Vector3(x + y, groundHeight, z); if (count < particles.Length -1) { count++; } else { UpdateDisplay(particles); return; } } } } } private void UpdateDisplay(Particle[] particles) { m_ParticleEmitter.particles = particles; } }