Who hasn't heard of YouTube today? It is perhaps the second most popular search engine after Google.

While Google browses the web for any or all kinds of content, YouTube performs similar browsing functions, but for videos. It also serves as a video-sharing social media platform, and allows users to upload, view, interact, and share videos. Additionally, it also provides a customized feed for each user among many other features. From entertainment, to arts and crafts, to cooking, and even education, you can find content regarding every topic on YouTube.

The features that YouTube provides are brilliant, and mostly with excellent performance, but how does it manage all these different features on a single platform? Systems like YouTube have a large system architecture that consists of multiple components, with each component performing a specific task. These components are responsible for how the overall system or the application behaves and functions.

This lesson aims to uncover how a large-scale application such as YouTube operates. More specifically, we will examine the entire system architecture, and understand the different components involved in the process. We will also have a look at the algorithms that internally work within YouTube that are responsible for personalized user content.