diff --git a/src/main.rs b/src/main.rs
index 3e96ce9..903b7d5 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,7 +1,11 @@
 #![allow(dead_code)]
+#![allow(unused_imports)]
+//Use our ray module
 mod ray;
-use nalgebra::{Matrix4, Vector4};
 use ray::Ray;
+//Use linear algebra module
+use nalgebra::Vector4;
+//Use modules for wgpu
 use std::borrow::Cow;
 use winit::{
     event::{Event, WindowEvent},
@@ -9,8 +13,8 @@ use winit::{
     window::Window,
 };
 
+//MAIN ---------------------------------------------------------------------------------
 fn main() {
-    let x = Vector4::new(1.0, 1.0, 1.0, 1.0);
-    let mat_a = Matrix4::from_diagonal_element(0.12);
-    println!("mat_a*x = {}", { mat_a * x });
+    println!("Hello world");
 }
+//NEXT ---------------------------------------------------------------------------------
diff --git a/src/ray.rs b/src/ray.rs
new file mode 100644
index 0000000..e8fdb88
--- /dev/null
+++ b/src/ray.rs
@@ -0,0 +1,15 @@
+use nalgebra::Vector4;
+
+pub struct Ray {
+    a: Vector4<f32>,
+    b: Vector4<f32>,
+}
+
+impl Ray {
+    fn new(_a: Vector4<f32>, _b: Vector4<f32>) -> Ray {
+        Ray { a: _a, b: _b }
+    }
+    fn at_t(self, t: f32) -> Vector4<f32> {
+        self.a + self.b * t
+    }
+}