How Data Travels
When you press play on a streaming service, your device sends a request to a server, which is a powerful computer that stores movies and shows. That server breaks the video into tiny pieces called packets and sends them through the internet to your home. Your device receives these packets, puts them back together in the correct order, and displays them on your screen. This all happens so quickly that you see the video almost instantly.
Video Compression
Streaming services use compression technology to make video files much smaller without losing quality. This is important because smaller files travel faster through the internet. The compression removes some information from the video that human eyes cannot notice anyway. Popular compression formats include H.264 and H.265, which can reduce a video to one-tenth of its original size.
Adaptive Streaming
Streaming services adjust video quality based on your internet speed. If your connection is slow, the service automatically lowers the quality so the video plays smoothly without stopping. When your connection gets faster, the quality improves. This automatic adjustment happens in real-time without you having to do anything, ensuring the best possible viewing experience.
Content Storage and Servers
Streaming companies store copies of their movies and shows on servers located in different parts of the world. When you request content, your device connects to the server closest to you to reduce delays. Having servers in many locations helps deliver content faster and reduces the burden on any single server.
Buffering Process
Before playing video, streaming services download a small amount of content ahead of what you are currently watching. This buffer, usually a few seconds of video, is stored temporarily on your device's memory. If your internet connection briefly slows down, this buffer allows the video to keep playing without interruption. Once you finish watching that buffered content, more is downloaded automatically. 
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