Keno doesn't just resemble a lottery game - it really is a lotto game. It's believed that perhaps it wasn't referred to as such at some point over the game's 3,000 year history because of taxes are laws that might have been put in place, so to keep the game going, they called it Keno instead of the lotto. It's believed that the game was initially invented by the Chinese in order to fund the Great Wall of China construction.
Initially the game was played with Chinese characters - 120 in total, which were later reduced to 90. The game came to the United States with immigrants from China in the 19th Century, many of which were railroad workers. Around this time, the game was again reduced from using 90 characters to using 80. When Keno first arrived in the United States, it was illegal, but that didn't stop the immigrants from playing it in big cities like San Francisco. When the game came to the United States it was called the Chinese Lottery, and although some English Americans started to develop an interest in the game, they had some trouble with the Chinese characters used. In order to make it appeal to a more widespread audience of people, around the 20th century, Keno operators began using Arabic numbers rather than the Chinese ones which could more easily be differentiated by English speaking players.
In 1931, many forms of gambling were legalized in Nevada, however, the lottery, even the Chinese Lottery was not made legal at this time. In order to remain in operation, those running the Chinese Lottery changed the name to Race Horse Keno, with each number being called a horse. When the US Government finally made Lottery style games legal, the name was changed back to Keno, which couldn't have come at a better time, because taxes were also applied to horse racing. Some of the trend from that period of time has still stuck around however, some Keno operators still refer to their games as "races", which doesn't make a whole lot of sense to players who don't understand the history of the game.
Over the years, Nevada has changed the payout limit for the game. In 1963 when a limit was introduced, it was set at $25,000; in 1979 it was increased again to $50,000. However, in 1989 the Nevada Gaming Commission allowed casinos to set their own aggregate limits for each game, so now there is no cap on the maximum amount that can be won from the government; but the limits can vary from casino to casino.
Later, once machine games started to become popular in casinos, Video Keno was created to provide players with a convenient electric version of the game that offers instant winning options to players. It first started in China, using original Chinese characters, and then was converted to an English version. The Video version of Keno is popular because it gives players almost immediate gratification instead of waiting for players to join in on the game and for the pool to increase.
Keno is a game that's also available in scratch tickets, or players at a casino can join in on the game, leaving their bets and then moving onto play something else so it's a game that's flexible, and easy to play.