
.NET is a free, open-source, cross-platform development platform from Microsoft for building web, desktop, mobile, cloud, and more.
.NET Core started as the cross-platform, modular, high-performance rewrite of .NET and has since unified into .NET 5+ (often just called ".NET").
Key characteristics:
1. Cross-platform — Windows, Linux, macOS
2. High performance — Kestrel, Span<T>, async I/O
3. Unified platform — one BCL, many app models (ASP.NET Core, MAUI, Worker Services)
4. Open source — developed in the open on GitHub
Architecture impact: Understanding the evolution from .NET Framework to .NET Core to unified .NET is essential for making migration and architecture decisions.
Reference:
TaskLoco™ — The Sticky Note GOAT