Stadia is Google's cloud gaming service that allows users to stream video games to various devices through online access, without requiring specialized gaming hardware. It can stream games up to 4K resolution at 60 frames per second. Stadia is accessible through the Google Chrome browser on desktops and laptops, as well as on smartphones, tablets, and smart TVs connected through Chromecast. Key characteristics include being platform independent, simple to use without gaming hardware, and reliable through cloud computing power. However, the service relies on high-speed internet, so performance may be impacted in remote areas with limited connectivity.