Ffff

"Blu-spec CD is a specification for an improved version of a conventional Audio CD, introduced by Sony Music Entertainment. Instead of a traditional infra-red laser, a blue laser is used for recording the pits on the CD master that is needed for disc replication. The blue laser creates more precise pits, causing less distortion in the optical read-out process and supposedly resulting in higher-quality audio."

On a semi-related note, tehslugbug has been making videos about things and how they work:

Tape flanging video
tape flanging video II: record flanging video
cd player video