Welcome to Pathfinding Algorithms! 🗺️

You open a maps app to go from point A to point B. The app shows you several routes and picks the fastest one. How does it do that? Behind the scenes, it’s using pathfinding algorithms like Dijkstra and A*.

This interactive tutorial will teach you how these algorithms work by building a small grid world. You’ll see them in action, step by step, and understand when to use each one.

What You’ll Learn

By the end of this tutorial, you’ll be able to:

• ✅ Model grids as graphs - Turn a 2D grid into nodes and edges
• ✅ Understand Dijkstra’s algorithm - Find the cheapest path by exploring outward
• ✅ Master A search* - Use heuristics to find paths faster
• ✅ Compare algorithms - See when each one performs better
• ✅ Implement both - Write working code for pathfinding
• ✅ Make informed choices - Know which algorithm fits your problem

Tutorial Structure

This tutorial is divided into 7 interactive pages (approximately 35 minutes):

1. Introduction (5 min) - How computers find paths and real-world scenarios
2. From Grid to Graph (5 min) - Converting a 2D grid into a graph structure
3. Dijkstra’s Algorithm (7 min) - Finding the cheapest path step by step
4. Heuristics and A* (7 min) - Using smart guesses to speed up search
5. Trade-offs (4 min) - When to use Dijkstra vs A*
6. Implementation (5 min) - Code walkthrough with working examples
7. Mini Project (2 min) - Build your own pathfinding toy

Interactive Features

Throughout this tutorial, you’ll experience:

• 🎮 Interactive Grids - Build and modify grids with walls and obstacles
• 🎬 Algorithm Visualizations - Watch Dijkstra and A* run step by step
• 📊 Side-by-Side Comparisons - See how algorithms differ in real-time
• 🧮 Live Code Examples - Run and modify pathfinding code
• ✅ Knowledge Checks - Test your understanding with quizzes

Prerequisites

Before starting, you should have:

• Basic understanding of arrays and dictionaries/maps
• Familiarity with one programming language (Python, JavaScript, C#, or Java)
• Basic knowledge of Big-O notation (helpful but not required)

Don’t worry if you’re not an expert - we’ll explain concepts as we go!

Estimated Time

⏱️ 35 minutes to complete all 7 pages

You can take breaks between pages and resume anytime. Your progress will be tracked as you navigate through the tutorial.

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What is Pathfinding?

Quick Preview: Pathfinding algorithms find the shortest or cheapest path between two points in a graph. Dijkstra’s algorithm explores all directions equally, while A* uses heuristics to focus the search toward the goal.

Why it matters: These algorithms power navigation apps, game AI, network routing, and robot navigation. Understanding them helps you solve many real-world problems.

Ready to start? Click the button above to begin your pathfinding journey!