1. Design Twitter. asked by Twitter.
  2. How do you build tiny URL. asked by Google.
  3. Design Instagram. asked by Facebook.
  4. Design Dropbox. asked by Dropbox.
    1. Ensure to think about handle large file sizes.
  5. Design YouTube. asked by Wealthfront.
    1. Ensure to think about handle large file sizes.
  6. Design WhatsApp. asked by Facebook.
    1. Ensure to think about real-time nature of these system.
  7. Design Uber. asked by Google.
    1. Ensure to think about real-time nature of these system.
  8. Design Reddit. asked by Reddit, Netflix.
    1. Think about the imbalance between read and write volumes in these systems.
  9. Design a Web Crawler. asked by Google.
  10. Design Airbnb search. asked by Airbnb.

Reference