C# Programming Language

C#

Paradigm	Multi-paradigm (object-oriented, imperative, functional, component-oriented)
Designed by	Anders Hejlsberg
Developer	Microsoft
First appeared	2000
Stable release	C# 12 (2023)
Typing discipline	Static, strong, safe, nominative, partially inferred
Platform	.NET
License	Open-source (MIT)

C# (pronounced "C-sharp") is a modern, object-oriented programming language developed by Microsoft. It was first released in 2000 as part of the .NET Framework. The language was designed by Anders Hejlsberg, who also created Turbo Pascal and Delphi.

History

1999–2000: Microsoft begins developing C# for the .NET project.
2000: First announced at the Professional Developers Conference (PDC).
2002: Released with .NET Framework 1.0.
2005: C# 2.0 adds generics, nullable types, and anonymous methods.
2007–2010: C# 3.0 and 4.0 add LINQ, lambdas, and dynamic binding.
2015: C# 6.0 introduces string interpolation and simplified syntax.
2017: C# 7.x adds tuples, pattern matching, local functions.
2020+: With .NET 5–8, C# becomes cross-platform with records and top-level statements.

Design Goals

Simplicity – Easy to learn for developers familiar with C, C++, Java.
Modernity – Garbage collection, type safety, safe code.
Object-Oriented – Everything revolves around objects and types.
Component-Oriented – Supports modular, reusable software design.
Interoperability – Works with the .NET ecosystem.

Example Code

Hello World

using System;

class Program
{
    static void Main()
    {
        Console.WriteLine("Hello, World!");
    }
}

Basic Class Example

using System;

public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }

    public void Greet()
    {
        Console.WriteLine($"Hello, my name is {Name} and I am {Age} years old.");
    }
}

class Program
{
    static void Main()
    {
        Person p = new Person { Name = "Alice", Age = 30 };
        p.Greet();
    }
}

LINQ Example

using System;
using System.Linq;

class Program
{
    static void Main()
    {
        int[] numbers = { 1, 2, 3, 4, 5 };

        var evenNumbers = numbers.Where(n => n % 2 == 0);

        Console.WriteLine("Even numbers:");
        foreach (var num in evenNumbers)
        {
            Console.WriteLine(num);
        }
    }
}

Modern Usage

Windows apps – WPF, WinForms, UWP
Web development – ASP.NET Core
Game development – Unity Engine
Cloud services – Azure APIs
Cross-platform apps – .NET MAUI, Xamarin

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