A Freemium is a business model that could apply to video games. Quoted from Wikipedia,

A freemium a business model by which a product or service (typically a digital offering such as software, media, games or web services) is provided free of charge, but a premium is charged for advanced features, functionality, or virtual goods. The word "freemium" is a portmanteau combining the two aspects of the business model: "free" and "premium".

A Freemium is a general term and a business model that refers to a product that is offered free of charge while a micropayment is charged for users to access premium features and virtual goods. Quoted from Wikipedia:

A freemium is a business model by which a product or service (typically a digital offering such as software, media, games or web services) is provided free of charge, but a premium is charged for advanced features, functionality, or virtual goods. The word "freemium" is a portmanteau combining the two aspects of the business model: "free" and "premium".