CDs reproduce 44,100 samples per second. Which has a maximum frequency reproduction of 22,050 Hz, or just a hair past the upper limit of human hearing. In this way CDs can theoretically reproduce any frequency in the human hearing range.
Phil Zimmermann created the first version of PGP encryption in 1991. Pretty Good Privacy (PGP) is a data encryption and decryption computer program that provides cryptographic privacy and authentication for data communication. PGP is often used for signing, encrypting and decrypting texts, E-mails, files, directories and whole disk partitions to increase the security of e-mail communications.
The word "laser" is actually an acronym for light amplification by stimulated emission of radiation. Atoms or molecules of the active medium that have been excited to a higher energy level are stimulated by a passing photon to relax to a lower energy level and emit a photon that is indistinguishable from the passing photon, thereby increasing the number of photons like the incident one.
Extension cords can be a tripping hazard, and can be easily damaged, causing an unsafe situation. There are many ways of safely getting power to each work place, where wiring is protected and concealed.