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@@ -78,6 +78,7 @@ This is primarly material and resources for beginners, if you're a rock-start ch
 - [WebGL Lessons — Fragment Shaders](https://github.com/Jam3/jam3-lesson-webgl-shader-intro) - A brief introduction to fragment shaders.
 - [WebGL Lessons — ThreeJS Shaders](https://github.com/Jam3/jam3-lesson-webgl-shader-threejs) - Using custom vertex and fragment shaders in ThreeJS.
 - [ThreeJS post-proces example](https://github.com/Jam3/threejs-post-process-example) - example of post-processing effects in ThreeJS.
+- [Introduction to shaders](https://aerotwist.com/tutorials/an-introduction-to-shaders-part-1/) - Part 1 of an introduction to shaders using threejs.
 - [Ray Marching and Signed Distance Functions](http://www.scratchapixel.com/lessons/3d-basic-rendering/introduction-to-ray-tracing) - Introduction to ray tracing.
 - [Introduction to Ray Tracing](http://jamie-wong.com/2016/07/15/ray-marching-signed-distance-functions/) - A simple method for creating 3D images.
 - [GLSL lighting walkthrough](https://github.com/stackgl/glsl-lighting-walkthrough) - Phong shading tutorial with glslify.