The magic behind Steam streaming is based on a technology called cloud gaming. essentially, it allows you to play games that are stored on remote servers, rather than on your local device. This means that you don't need a powerful computer to play the latest games, because all the processing power is happening in the cloud.
It's kinda like Netflix, but instead of streaming movies and TV shows, you're streaming games. You can start playing a game on one device, and then pick up where you left off on another device, without having to worry about saving your progress or transferring files. It's super convenient, and it's changing the way we think about gaming.
How does a Steam Turbine Work? - YouTube
But how does it actually work? Well, when you start a game on Steam, your device sends a request to the Steam servers, which then start running the game on a remote computer. The video and audio are then streamed back to your device, where you can play the game in real-time. It's like having a virtual gaming PC that you can access from anywhere.