"Ad-supported" refers to a business model where a service or product is offered for free or at a reduced cost, funded primarily by advertisements. This means that users can access content, such as streaming services or websites, without paying a subscription fee, but they will encounter ads during their experience. This model is commonly used by platforms like YouTube and Spotify, where advertisers pay to display their ads to users. While this allows for free access, it can also lead to interruptions and a less personalized experience compared to ad-free options.