SignalR is used by the ASP.Net framework to enable real-time data transfer in web applications between the server and client.
So a recent project with Blazor required that we keep with HTML tables to display data. The JS DataTables provides a sexy way of displaying data on a web page. DataTables provide pagination, search and data sorting by default, and a ton of other useful options.
The simplified answer is that WebAssembly allows applications written in high level languages, like C#, to be downloaded and then run in your browser.