Interactive & Visual Interview Prep for DSA and System Design
Every lesson is an interactive simulation, so you learn how it works, why it works and when to use it, instead of memorising the answer.
- Every lesson is a live simulation
- 15 to 25 minutes per lesson
- 100% free
Interactive demo
Array: slot 3 is 12, not it. Tree: found it in 3.
- Watch the race
- Pick a number
- Why it wins
Choose what to learn
Try a simulation now
Which data structure is fastest? It depends on what you ask it to do.
Data Structures & Algorithms: The Big Picture
Every data structure answers one question: which operations must be fast? Every algorithm follows a handful of patterns. Read this before your first lesson.
- No data structure is fastest at everything — it depends on the operations you need.
- Six structures (array, linked list, hash map, tree, heap, graph) cover most interview problems.
- Most interview algorithms follow a small set of recurring patterns.
FAQ
Is it free?
Yes. Every lesson is free. Ads pay for hosting and new lessons, so you never pay. You only need an account to save progress.
Who is it for?
Students learning computing fundamentals from the ground up, and IT professionals preparing for interviews or refreshing core concepts. Each lesson starts with the basics and builds from there.
How is this different from practice sites like LeetCode?
Practice sites check whether your code passes test cases. TheLearningLoop shows why a structure behaves the way it does, so you can reason through a follow-up question instead of reciting a memorised answer.
How long does each lesson take?
Most take 15 to 25 minutes.