The worldwide video game market could grow from $137.9 billion this year to $180.1 billion by 2021, according to Newzoo. The research firm also expects the top five video game markets to generate nearly $98 billion in revenue this year.

Chart showing the top five video game markets in the world by revenue

Data source: Newzoo. Chart by author.

China famously banned video game consoles for 15 years (2000 to 2015) due to fears about their impact on children's development, but that merely turned PCs -- and later, mobile devices -- into its main gaming platforms.

China is now home to Tencent (OTC:TCEHY), the largest video game publisher in the world. Tencent's portfolio of games includes League of Legends, Clash of Clans, Arena of Valor, as well as stakes in Epic Games' Fortnite and PUBG Corporation's PlayerUnknown's Battlegrounds.

However, questions about the future of China's gaming industry recently arose after regulators halted approvals of new games due to leadership changes and content concerns.

The split between PC, console, and mobile games varies by country, but the growth of mobile games is a common thread across these markets. Newzoo expects mobile games to generate 51% of the world's gaming revenue this year, fueled by the widespread use of smartphones and the accessibility of touchscreen-based games.