Defining Characteristics of Cross-Sectional Studies. Think of a cross-sectional study as a snapshot of a particular group of people at a given point in time. Unlike longitudinal studies that look at a group of people over an extended period, cross-sectional studies are used to describe what is happening at the present moment.
Dec. 3, 1992: The first text message Papworth, a former developer at Sema Group Telecoms, sends the world's first SMS greeting to his friend Richard Jarvis, who at the time worked at U.K. service Vodafone. Jarvis couldn't say Merry Christmas back, because his brick-sized Orbitel 901 phone had no way of inputting text.
Who Invented Pong? One of the earliest forms of arcade video games, Pong is a two-dimensional tennis game. The primary aim of the game is to beat opponents by scoring higher. Released in 1972, this important development eventually led to a boom in the video game industry. With its rich and colorful history, it is but great to take a quick look at the start of this early video game form including who invented Pong. The Invention of Pong.