contents(system design): gaurav sen system design playlist (#575)

apps/website/contents/system-design.md

@@ -43,6 +43,7 @@ System design content is still work-in-progress, but the following are some reso
 - ["Grokking the Advanced System Design Interview" by Design Gurus](https://designgurus.org/link/kJSIoU?url=https%3A%2F%2Fdesigngurus.org%2Fcourse%3Fcourseid%3Dgrokking-the-advanced-system-design-interview) - I haven't tried this but it's by the same people who created "Grokking the System Design Interview", so it should be good! In my opinion you probably wouldn't need this unless you're very senior or going for a specialist position.
 - ["Best of System Design" package by Design Gurus](https://designgurus.org/link/kJSIoU?url=https%3A%2F%2Fdesigngurus.org%2Fbundles%3Fbundle_id%3Dbuy-both-system-design-courses) - This bundle allows you to purchase both System Design interview courses by Design Gurus at a discount. Best of all, it's lifetime and not subscription-based.
 - ["System Design Interview Course" by Exponent](https://www.tryexponent.com/courses/system-design-interview?ref=techinterviewhandbook) - This course covers system designs basics and has a huge database of popular system design questions with videos of mock interviews. Some of the questions have text answers and a database schema and APIs for reference (which I find helpful). While the subscription might be a little pricey for just the system design interviews content, they also offer quality technical content for [Data Structures](https://www.tryexponent.com/courses/swe-practice?ref=techinterviewhandbook), [Algorithms](https://www.tryexponent.com/courses/algorithms?ref=techinterviewhandbook) and [Behavioral Interviews](https://www.tryexponent.com/courses/behavioral?ref=techinterviewhandbook). The convenience of a one-stop platform which covers all aspects of technical interview preparation is very enticing.
+- ["Gaurav Sen Youtube - System Design Playlist"](https://youtu.be/xpDnVSmNFX0) - Gaurav Sen is a popular YouTuber who has gained a lot of recognition for his system design videos. His playlist on System Design provides a comprehensive guide for software engineers who are preparing for technical interviews or want to learn more about how to design scalable systems. The playlist consists of multiple videos, each video covering a different topic related to system design. The videos are designed in a way that simplifies complex topics and makes it easy to understand for beginners.
 
 ## Free resources