Typically refers to optical media that contain two layers on a single side in order to double or nearly double the storage capacity. Also called "double layer." See DVD-9 and Blu-ray.
"dual layer." YourDictionary, n.d. Web. 17 August 2018. <http://www.yourdictionary.com/dual-layer>.
dual layer. (n.d.). Retrieved August 17th, 2018, from http://www.yourdictionary.com/dual-layer