In the video game industry, AAA (Triple-A) is a buzzword used to classify video games produced or distributed by a mid-sized or major publisher, which typically have higher development and marketing budgets than other tiers of games.
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The term “AAA” began to be used in the late 1990s by game retailers attempting to gauge interest in upcoming titles, and first appeared in print in a press release from Infogrames in June 2000. The term was likely borrowed from the credit industry’s bond ratings, where “AAA” bonds represent the safest investment opportunity and are the most likely to meet their financial goals.

https://en.wikipedia.org/wiki/AAA_(video_game_industry)