Simple Definition:

Mass media refers to various forms of communication that reach a large audience [a large group of people]. It includes mediums such as television, radio, newspapers, magazines, and the internet (websites and social media platforms). For example, when you watch a TV show, listen to the radio, read a newspaper, or browse the internet, you are consuming mass media.

Very Simple Definition:

Mass media is a way of sharing information with many people. It includes things like TV, radio, newspapers, magazines, and the internet. For example, when you watch TV or listen to the radio, you are using mass media.