The framework is built on .NET that runs in the browser via WebAssembly, and is based on HTML, CSS and other standard web technologies. If Blazor sounds new to you that’s because it has only been in development since 2018, initially as an experimental project.
Blazor has two separate execution modes with the biggest difference being the way the application is deployed. The first one is called Client-side and basically does what the previous paragraph described – this is the new and innovative concept for C# in the browser, it’s what Blazor is all about. Blazor’s other execution mode is called Server-side Blazor and in this configuration, Blazor operates more closely to how previous ASP.NET technologies worked. This mode is great for compatibility with existing applications.
For more information about Blazor check out our blog.
For more information on the differences between Blazor’s 2 execution modes, check out another of our FAQ entries.