Learn C#
Structured lessons from the basics up — follow the path below in order, at your own pace.
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1
Level 1 — Beginner Beginner 26 lessons
Start here if you have never written a line of C# before. Work through these lessons in order — each one builds on the last.
Lessons in this module
What Is C#? Why Learn C#? Installing the .NET SDK Setting Up Your Development Environment Your First C# Program How C# Code Runs: Compiling and the CLR Variables & Data Types Type Casting & Conversion Operators Strings String Interpolation Reading User Input Conditionals Switch Statements & Expressions Loops Arrays Methods Method Overloading & Optional Parameters Introduction to Classes & Objects Constructors Properties Access Modifiers Static Members Namespaces Comments & Code Style Debugging Basics -
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Beginner Projects Beginner 1 lesson
Build these with nothing but what Level 1 covered — a console app, methods, and classes. Read two numbers and an operator (+ - * /) with…
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3
Level 2 — Intermediate Intermediate 20 lessons
These lessons cover object-oriented programming in depth, collections, LINQ, async/await, and the everyday tools of a working C# developer.
Lessons in this module
Object-Oriented Programming: The Big Picture Inheritance Polymorphism Abstract Classes Interfaces Encapsulation in Practice Enums Exception Handling Custom Exceptions Generics Collections in Depth Delegates & Events Lambda Expressions, Func, and Action LINQ Nullable Types & Null Safety Records File I/O Async and Await Unit Testing with xUnit Debugging & Logging -
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Intermediate Projects Intermediate 1 lesson
Build these using OOP, LINQ, and async/await from Level 2. Model an Account class (encapsulated Balance property, Deposit/Withdraw that…
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5
Level 3 — Advanced Advanced 16 lessons
These lessons cover concurrency, reflection, dependency injection, and how a real C# service is built with ASP.NET Core and shipped.
Lessons in this module
Advanced Generics & Constraints Advanced LINQ & Deferred Execution Multithreading with the Task Parallel Library Concurrent Collections & Synchronization Pattern Matching in Depth Reflection & Attributes Dependency Injection Design Patterns in C# Memory Management & Garbage Collection Building a Web API with ASP.NET Core Entity Framework Core & Databases Testing Strategies Performance Optimization & Profiling Security Fundamentals Packaging & Deployment The .NET Ecosystem: Beyond the Console -
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Advanced Projects Advanced 1 lesson
Build these using async/await, EF Core, and ASP.NET Core from Level 3. Build a small ASP.NET Core Web API with GET/POST/DELETE endpoints…
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7
What You Should Know Now — and What's Next 1 lesson
Core syntax: variables, properties, control flow, arrays, methods Object-oriented programming: inheritance, polymorphism, interfaces, and…