Roadmap › .NET Internals — CLR, CTS, CLS, IL, JIT, Memory Management & Garbage Collection › Module: Platform and Compilation
Lessons in this course (11)
1. .NET Framework vs .NET Core vs .NET 5+ — the history explained
Basic★ Must knowLesson 1 of 11
| .NET Framework | .NET Core 1–3.1 | .NET 5+ | |
|---|---|---|---|
| Years | 2002–2019 (4.8.1 in 2022) | 2016–2019 | 2020 → |
| OS | Windows only | Windows, Linux, macOS | Windows, Linux, macOS, mobile (MAUI), WebAssembly |
| Source | Closed (reference source available) | Open source (MIT) | Open source |
| Deployment | Machine-wide install, part of Windows | Side-by-side, self-contained possible | Same + single-file, Native AOT |
| Web | ASP.NET Web Forms, MVC 5, Web API 2 | ASP.NET Core | ASP.NET Core |
| Performance | Good | Much faster | Fastest; improves every release |
| Status | Maintenance only | Out of support | Active |
Mono (2004, open source, by Ximian → Xamarin → Microsoft) ran .NET on Linux/macOS/mobile and powers Unity and Xamarin; today its runtime is used inside .NET for mobile and WebAssembly.
Interview tip: "Why did they skip .NET 4?" — to avoid confusion with .NET Framework 4.x; .NET 5 dropped "Core" from the name because it became the .NET going forward.