Introduction to .NET Core

Welcome to the introduction to .NET Core! This document provides a high-level overview of what .NET Core is, its key principles, and how it differs from previous .NET Framework versions. Whether you are a seasoned developer or new to the .NET ecosystem, this guide will help you understand the foundational concepts of this powerful, cross-platform, open-source framework.

What is .NET Core?

.NET Core is a free, cross-platform, open-source framework for building various types of applications, including web apps, microservices, IoT apps, and mobile backends. It is the successor to the .NET Framework and is designed for modern development practices.

Key characteristics of .NET Core include:

Cross-Platform: Runs on Windows, macOS, and Linux.
Open-Source: Developed and maintained by Microsoft and a vibrant community on GitHub.
High-Performance: Optimized for speed and efficiency.
Modular: Designed with a modular architecture, allowing you to include only the components you need.
Cloud-Ready: Built with cloud deployments and microservices in mind.

Key Principles

.NET Core is guided by several core principles that drive its design and development:

1. Performance

Performance is a top priority. .NET Core has undergone significant optimizations to achieve industry-leading benchmarks for speed and throughput. This makes it an excellent choice for performance-critical applications and scenarios like microservices.

2. Developer Productivity

The framework aims to empower developers with tools and features that streamline the development process. This includes improved project file formats, enhanced debugging capabilities, and a rich set of libraries.

3. Modern Workloads

.NET Core is designed to support a wide range of modern application types. From lightweight microservices to scalable web APIs and real-time applications, .NET Core provides the foundation you need.

4. Cloud-Native

With the rise of cloud computing, .NET Core is built to be cloud-native. It supports containerization (Docker), microservices architectures, and seamless deployment to cloud platforms like Azure, AWS, and Google Cloud.

.NET Core vs. .NET Framework

While .NET Core shares many similarities with the .NET Framework, there are significant differences:

Platform: .NET Framework is Windows-only, whereas .NET Core is cross-platform.
Deployment: .NET Core supports self-contained deployments, allowing you to bundle the .NET runtime with your application, making it independent of globally installed versions.
Open-Source: .NET Core is open-source and community-driven, fostering greater transparency and collaboration.
Modularity: .NET Core's modular design allows for smaller footprints and more targeted dependencies.
Tooling: .NET Core introduced new command-line tools (CLI) for project management, building, and testing, complementing existing IDE support.

            Note: As of .NET 5, .NET Core, .NET Framework, and Xamarin are unified under a single ".NET" name. This guide focuses on the foundational principles established by .NET Core, which continue to define the modern .NET platform.
        

Getting Started

To start building applications with .NET Core, you'll need to install the .NET SDK. You can find detailed instructions on the Getting Started page.

Once installed, you can use the .NET CLI to create, build, and run your first application:


dotnet new console -o MyFirstApp
cd MyFirstApp
dotnet run

This will create a simple console application and run it. Explore the generated files to understand the project structure.

Conclusion

.NET Core represents a significant evolution in the .NET ecosystem, offering a powerful, flexible, and high-performance platform for a wide array of application development needs. Its cross-platform nature, open-source model, and focus on modern development practices make it an essential technology for today's developers.

.NET Docs