Object-Oriented Design
Master core concepts with guided docs and AI explainers for difficult jargon.
Tier 1 -- Foundations
23 docsCore Concepts
OOP Pillars
SOLID Principles
Creational Patterns
Structural Patterns
Tier 2
6 docsTic-Tac-Toe — OOD Interview Walkthrough15 min read · tic-tac-toe
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Vending Machine — OOD Interview Walkthrough15 min read · vending-machine
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Traffic Light System — OOD Interview Walkthrough12 min read · traffic-light-system
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Logging Framework — OOD Interview Walkthrough15 min read · logging-framework
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Text Editor Undo/Redo — OOD Interview Walkthrough15 min read · text-editor-undo-redo
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Meeting Scheduler — OOD Interview Walkthrough19 min read · meeting-scheduler
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Tier 3
13 docsParking Lot — OOD Interview Walkthrough18 min read · parking-lot
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Library Management System — OOD Interview Walkthrough35 min read · library-management-system
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ATM Machine — OOD Interview Walkthrough35 min read · atm-machine
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LRU Cache12 min read · lru-cache
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Snake and Ladder17 min read · snake-and-ladder
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Blackjack21 min read · blackjack
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Elevator System13 min read · elevator-system
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OOD Interview: Movie Ticket Booking System (BookMyShow)34 min read · movie-ticket-booking
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Restaurant Food Ordering System15 min read · restaurant-food-ordering-system
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Hotel Management System — OOD Interview Walkthrough37 min read · hotel-management-system
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Car Rental System — OOD Interview Walkthrough38 min read · car-rental-system
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Amazon Locker15 min read · amazon-locker
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Splitwise18 min read · splitwise
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Tier 4
9 docsFile System31 min read · file-system
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Unix `find` Command30 min read · unix-find-command
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Chess Game45 min read · chess-game
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Course Registration System43 min read · course-registration-system
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Online Shopping System — OOD Interview Walkthrough44 min read · online-shopping-system
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Music Streaming Service — OOD Interview Walkthrough25 min read · music-streaming-service
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Airline Management System — OOD Interview Walkthrough24 min read · airline-management-system
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Ride-Sharing Service — OOD Interview Walkthrough34 min read · ride-sharing-service
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Stock Brokerage Platform — OOD Interview Walkthrough46 min read · stock-brokerage-platform
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Tier 5
5 docsBlocking Queue14 min read · blocking-queue
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Thread-Safe Cache11 min read · thread-safe-cache
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Concurrent HashMap10 min read · concurrent-hashmap
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Pub/Sub System14 min read · pub-sub-system
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Distributed Lock Service18 min read · distributed-lock-service
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