01Distributed Metrics Logging & Aggregation
02Distributed Stream Processing System (like Kafka)
03Key-Value Store
04Top K Most Shared Articles in Time Windows
05API Rate Limiter
06Collect Performance Metrics from Thousands of Servers
07Google Calendar
08Distributed Queue (like RabbitMQ)
09Google Analytics — User Analytics Dashboard
10Sorting Large Data Sets
11Top K Elements — App Store Rankings / Amazon Bestsellers
12Dropbox / Google Drive
13Distributed Job Scheduler
14Notification Service at Scale
15Surge Pricing System (Uber)
16Netflix — Limit Concurrent Screens
17ETA Service & Location Sharing (Uber)
18Hotel Booking System
19A/B Testing System (Optimizely)
20Price Alert System (Amazon / Stock Prices)
21IoC / Dependency Injection Framework
22Credit Card Processing System
23Count Facebook Likes (High-Profile Users)
24Control Plane for Distributed Database
25User Login & Authentication System
26Weather Application
27Collaborative Document System (Google Docs / Notion)
28Facebook Marketplace
29Monitor Health of a Cluster
30Find a Rider/Driver (Uber Dispatch)
31Distributed Tracing System
32Distribute 6M Free Burgers in 1 Hour
33File Downloader Library
34View Latest Stock Prices Worldwide
35Photo Sharing Platform (Flickr / Google Photos)
36On-Call Escalation System
37Wire Transfer API
38Live Comments Feature (Facebook)
39Count Users Viewing a Page
40Facebook Likes with Live Updates
41Migrate Large Data to Google Cloud
42Distributed Botnet (Defense-Focused)
43Distributed File Transfer (BitTorrent)
44Parts Compatibility for eCommerce
45Ads Management & Display System
46API (Application Programming Interface)
47Load Balancer
48Caching Strategies
49Content Delivery Network (CDN)
50Database Indexing
51Pagination Strategies
52Idempotency
53Database Replication
54Database Sharding
55Microservices Architecture
56Distributed Locking
57Consistency vs Availability (CAP Theorem)
58WebSockets
59Circuit Breaker
60Retry & Exponential Backoff
61Horizontal vs Vertical Scaling
46API (Application Programming Interface)
47Load Balancer
48Caching Strategies
49Content Delivery Network (CDN)
50Database Indexing
51Pagination Strategies
52Idempotency
53Database Replication
54Database Sharding
55Microservices Architecture
56Distributed Locking
57Consistency vs Availability (CAP Theorem)
58WebSockets
59Circuit Breaker
60Retry & Exponential Backoff
61Horizontal vs Vertical Scaling
46API (Application Programming Interface)
47Load Balancer
48Caching Strategies
49Content Delivery Network (CDN)
50Database Indexing
51Pagination Strategies
52Idempotency
53Database Replication
54Database Sharding
55Microservices Architecture
56Distributed Locking
57Consistency vs Availability (CAP Theorem)
58WebSockets
59Circuit Breaker
60Retry & Exponential Backoff
61Horizontal vs Vertical Scaling