Blazor is a web framework for building web UI components (Razor components) that can be hosted in different ways. Razor components can run server-side in ASP.NET Core (Blazor Server) or client-side in the browser on a WebAssembly-based .NET runtime (Blazor WebAssembly, Blazor WASM). 
Blazor Hybrid allows hosting Razor components in native mobile and desktop apps that render to an embedded Web View control.
Blazor is built on top of .NET and allows developers to use C instead of JavaScript to build interactive client-side web applications.

Blazor

A cross-platform app development framework that allows developers to build native apps for iOS, Android, and Windows using a single, shared codebase. It uses C# as its programming language and is known for its performance and scalability.

Xamarin

C# is a general-purpose high-level programming language supporting multiple paradigms. C# encompasses static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented, and component-oriented programming disciplines. 

F# is a functional-first, general-purpose, strongly typed, multi-paradigm programming language that encompasses functional, imperative, and object-oriented programming methods.

Visual Basic, originally called Visual Basic .NET, is a multi-paradigm, object-oriented programming language, implemented on .NET, Mono, and the .NET Framework. Microsoft launched VB.NET in 2002 as the successor to its original Visual Basic language, the last version of which was Visual Basic 6.0

.Net Framework

Blazor

Xamarin

C#

F#

VB.Net