Difference between Dual-Layer and Double-Sided DVD
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John Linneman on Twitter: "So it turns out not everyone is aware of the different media types used on PS2! Here's a guide! Blue disk = CD Silver = DVD (single layer) Gold = DVD-9 (dual layer) https://t.co/VTK64UUdfR" / Twitter
What's the Difference Between Dual-Layer and Double-Sided DVD's? - MajorGeeks
Blu-ray/ DVD Combo ROM Disc Technology, Enabling 33.5GB Storage Capacity