Introduction to C#

Welcome to our comprehensive C# learning portal! This introduction will give you a solid foundation in C# programming and prepare you for more advanced concepts in later lessons.

What is C#?

C# (pronounced "C-sharp") is a modern, object-oriented programming language developed by Microsoft as part of its .NET initiative. Since its first release in 2002, C# has evolved significantly and is now used for developing:

• Desktop applications (Windows Forms, WPF)
• Web applications (ASP.NET)
• Mobile applications (Xamarin, MAUI)
• Games (Unity)
• Cloud services (Azure)
• Internet of Things (IoT) applications

C# and .NET Ecosystem

C# is designed to be simple, modern, flexible, and versatile. Its syntax is similar to other C-style languages such as C, C++, and Java, making it easier to learn if you're already familiar with these languages.

Your First C# Program

Let's look at a simple "Hello World" program in C#. This is typically the first program you write when learning a new programming language:

using System;

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            // This is a comment
            Console.WriteLine("Hello, World!");
            
            // Wait for user input before closing
            Console.ReadKey();
        }
    }
}

Breaking Down the Code

Let's examine the components of this program:

• using System; - Includes the System namespace, which contains fundamental classes and base types
• namespace HelloWorld - Declares a namespace for your code
• class Program - Defines a class named Program
• static void Main(string[] args) - The entry point of your application
• Console.WriteLine("Hello, World!"); - Prints text to the console
• Console.ReadKey(); - Waits for a key press before closing the console window

Program Execution Flow

Why Learn C#?

There are many compelling reasons to learn C#:

• Versatility: C# can be used for almost any type of software development
• Large Community: Extensive resources, libraries, and community support
• Modern Features: Regular updates with modern programming features
• Cross-Platform: With .NET Core/.NET 5+, C# applications can run on Windows, macOS, and Linux
• Career Opportunities: High demand for C# developers in various industries

Getting Ready

In the next lesson, we'll set up your development environment so you can start writing and running C# code on your own computer. You'll learn how to install Visual Studio or Visual Studio Code, and we'll walk through creating your first project.