C# is a general-purpose, type-safe language designed for the .NET ecosystem. Microsoft and the open-source community evolve it with yearly releases while keeping backward compatibility for large codebases.
Core characteristics
- Static typing — compile-time checks;
varstill infers a fixed type - Managed execution — CLR + GC; use
IDisposablefor unmanaged resources - Multi-paradigm — OOP, functional LINQ, async/await, pattern matching
- Rich BCL — Base Class Library for collections, I/O, networking, and more
Typical build-run flow (local)
dotnet new console -n MyApp- Edit
Program.cs dotnet runcompiles IL and executes under the CLR
Where C# appears
ASP.NET Core APIs, Azure services, Unity games, Windows desktop tools, and enterprise line-of-business systems. Compare JVM careers with the Java track.
Important interview questions and answers
- Q: Is C# only for Windows?
A: No—.NET runs on Linux and macOS; ASP.NET Core is cross-platform. - Q: C# vs Java in one line?
A: Both are managed OOP languages; C# targets CLR with properties/LINQ/async keywords; Java targets JVM with its own libraries.
Self-check
- What command creates a new console project?
- Name one product category that commonly uses C#.
Tip: C# source uses .cs files compiled to IL assemblies—think JVM bytecode but for the .NET CLR.
Interview prep
- Is C# garbage collected?
Yes—managed objects on the CLR heap are reclaimed by a tracing GC; use
IDisposableandusingfor unmanaged resources.- Who uses C#?
ASP.NET Core teams, Azure services, Unity game studios, enterprise desktop apps, and organizations standardized on .NET.