What do we call a network whose elements may be separated by some distance? It usually involves two or more small networks and dedicated high-speed telephone lines.

The HF band is based on frequencies 3 to 30 Mhz. AM radio stations are in the HF band but normally are stated in kilohertz.

SPICE (Simulation Program with Integrated Circuit Emphasis) was introduced in May 1972 by the University of Berkeley, California.

A collection of atoms or molecules that can be excited to a higher energy state is called an active medium. Before lasing can occur, the active media is "pumped". The process of raising the atoms in the active media from a lower energy state to a higher state is like pumping water up from a well.

JVC (Japan Victor Corporation) and Matsushita (Panasonic) developed the VHS format to compete with Sony which developed the Beta format as the first home video cassette recorder. VHS originally stood for Vertical Helical Scan, but now means Video Home System.

RF is radio frequency. IF is intermediate frequency used inside the TV for processing. AF is audio frequency. SAP is second audio program which may have another language or other soundtrack as an option to the main soundtrack.

The first laser was a solid state laser. Solid state refers to any solid material like a glass rod. Diode lasers are very common because they are used to read compact disks and digital video disks in computers, CD players, and DVD players. Before diode lasers, the most common type of laser may have been the helium-neon laser, in which the active medium is a combination of the two gasses helium and neon.

On April 6, 1914, Hiram Percy Maxim proposed the formation of the American Radio Relay League.