Incremental games, also called idle games, clicker games or clicking games, are video games whose gameplay consists of the player performing simple actions (such as clicking on the screen) repeatedly to gain currency. This can be used to obtain items or abilities that increase the rate at which currency accrues. A common theme is to give the player sources of time-based income displayed as "buildings", such as factories or farms. Some incremental games require players to collect multiple currencies to progress through the game. In some games, even the clicking becomes unnecessary after a time, as the game plays itself, including in the player's absence, hence the moniker "idle game". Incremental games gained popularity in 2013 after the success of Cookie Clicker, although earlier games such as Cow Clicker and Candy Box were based on the same principles. In 2015, the gaming press observed such games again proliferating on the Steam game distribution platform with titles such as Clicker ...