Early history of video games
Throughout the rest of the 1960s, digital computer games were created by increasingly numerous programmers and sometimes sold commercially in catalogs. As the audience for video games expanded to more than a few dozen research institutions with the falling cost of computers, and programming languages that would run on multiple types of computers were created, a wider variety of games began to be developed. Video games transitioned into a new era in the early 1970s with the launch of the commercial video game industry in 1971 with the display of the coin-operated arcade game "Galaxy Game" and the release of the first arcade video game "Computer Space", and then in 1972 with the release of the immensely successful arcade game "Pong" and the first home video game console, the Magnavox Odyssey, which launched the first generation of video game consoles.
Space Invaders
As one of the earliest shooting games, "Space Invaders" set precedents and helped pave the way for future titles and for the shooting genre. "Space Invaders" popularized a more interactive style of gameplay with the enemies responding to the player controlled cannon's movement, and was the first video game to popularize the concept of achieving a high score, being the first to save the player's score. While earlier shooting games allowed the player to shoot at targets, "Space Invaders" was the first in which targets could fire back at the player. It was also the first game where players were given multiple lives, had to repel hordes of enemies, could take cover from enemy fire, and use destructible barriers, in addition to being the first game to use a continuous background soundtrack, with four simple diatonic descending bass notes repeating in a loop, which was dynamic and changed pace during stages, like a heartbeat sound that increases pace as enemies approached.