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.
2. Which consists of two plates separated by a dielectric and can store a charge?
Useful in tuning and filtering circuits, it blocks DC while passing AC. How much charge a capacitor can store is its capacitance, measured in farads.nn
3. What does AC and DC stand for in the electrical field?
Correct Answer: Alternating Current and Direct Current
Explanation:
Electricity is voltage and current. Voltage is electrical pressure, and current is the flow of charged particles. The difference between alternating current (AC) and direct current (DC) is that the electrons in an AC circuit regularly reverse their direction. In a DC circuit electrons always flow in the same direction.
On December 12, 1901, a radio transmission received by Guglielmo Marconi resulted in the first transmission of a transatlantic wireless signal (Morse Code) from Poldhu, Cornwall, to St. John's, Newfoundland.
6. Compact discs, (according to the original CD specifications) hold how many minutes of music?
According to many stories surrounding the origin of the compact disc, 74 minutes was settled on because it would comfortably contain all of Beethoven's 9th symphony on one disc. Although some stories reference a specific Sony higher-up who claimed this as his favorite piece of music, stories differ. All that's known for sure is that Sony insisted on this and won out over Phillips' original 60 minute proposal.
7. Sometimes computers and cache registers in a foodmart are connected to a UPS system. What does UPS mean?
An uninterruptable power supply (UPS) is a backup power supply, such as a battery, that provides emergency power in the event that power is lost from the main supply.
8. Who co-created the UNIX operating system in 1969 with Dennis Ritchie?