Lightning strikes, lasting less than a half-millionth of a second, often scorch the skin but don't cause internal burns. Just as crucial, most of the electricity in a lightning bolt does not pass through the body. Rather, it dissipates over the skin in what's known as a flashover. Vernon Cooray, a lightning scientist at Uppsala University in Sweden, explains the phenomenon by contrasting the ways a human body and a tree react when struck.
Human-computer interaction (HCI) is the study and planned design of human and computer activities. HCI uses productivity, safety and entertainment to support and fulfill human-computer activities and is applied to various types of computer systems, including air traffic control, nuclear processing, offices and computer gaming.
In its more general usage, a personal computer (PC) is a microcomputer designed for use by one person at a time. In its more general usage, a personal computer (PC) is a microcomputer designed for use by one person at a time. Prior to the PC, computers were designed for (and only affordable by) companies who attached terminals for multiple users to a single large computer whose resources were shared among all users.