• [ ] Design URL Shortener
• [ ] Design Search Autocomplete System
• [ ] Design Pastebin
• [ ] Design Uber
• [ ] Design Food Delivery Service
• [ ] Design Airbnb
• [ ] Design Instagram
• [ ] Design twitter
• [ ] Design Amazon
• [ ] Design Notification Service
• [ ] Design FB News Feed
• [ ] Design WhatsApp: read from hello interview
• [ ] Design Slack
• [ ] Design Live Comments
• [ ] Design Real Time Leaderboard
• [ ] Design Top K
• [ ] Design Likes Counting System
• [ ] Design News Aggregator
• [ ] Design Ad Click Aggregator
• [ ] Design Web crawler