Chapter 1 · Lesson 1

What is C#?

C# (pronounced "C-sharp") is a modern, object-oriented programming language developed by Microsoft. It was created by Anders Hejlsberg and released in 2000 as part of the .NET initiative.

Key Features:

Type Safe: Strong typing prevents many bugs
Modern Syntax: Clean, expressive, constantly evolving
Cross-Platform: .NET Core runs on Windows, Mac, Linux
Garbage Collected: Automatic memory management
Rich Ecosystem: Extensive standard library

Where C# is Used:

Game Development (Unity)
Web Applications (ASP.NET)
Desktop Apps (WPF, WinForms, MAUI)
Cloud Services (Azure)
Mobile Apps (Xamarin, MAUI)

C# Versions: C# evolves quickly. C# 12 is the latest, with features like primary constructors and collection expressions.

Code Examples

Hello Worldcsharp

// Modern C# (top-level statements)
Console.WriteLine("Hello, World!");

// Variables with type inference
var name = "C#";
var version = 12;

Console.WriteLine($"Welcome to {name} {version}!");

// Traditional class structure
public class Program
{
    public static void Main(string[] args)
    {
        Console.WriteLine("Hello from Main!");
        
        // String interpolation
        string language = "C#";
        int year = 2024;
        Console.WriteLine($"{language} in {year} is amazing!");
    }
}

Modern C# supports top-level statements for simple programs. The $ prefix enables string interpolation.

Quick Quiz

1. Who created C#?

Was this lesson helpful?

Code Examples

Hello Worldcsharp

// Modern C# (top-level statements)
Console.WriteLine("Hello, World!");

// Variables with type inference
var name = "C#";
var version = 12;

Console.WriteLine($"Welcome to {name} {version}!");

// Traditional class structure
public class Program
{
    public static void Main(string[] args)
    {
        Console.WriteLine("Hello from Main!");
        
        // String interpolation
        string language = "C#";
        int year = 2024;
        Console.WriteLine($"{language} in {year} is amazing!");
    }
}

Modern C# supports top-level statements for simple programs. The $ prefix enables string interpolation.