SignalR existed prior to the introduction of the ASP.NET Core family of framework versions, and it was simply designed as a library to cater to real-time communication between the server and its clients.

It leveraged and improved upon the use of the WebSockets technology, which we covered in the previous chapter. If you read around the World Wide Web (WWW), you will notice that most examples for SignalR explain its usage on real-time chat applications, and rightly so, but there are a lot of applicable situations where it can be utilized as well, including dashboards, real-time stock trade applications, and so on.

SignalR has been evolving and maturing as a technology, and consequently it works together with Blazor or Razor components, whose client-side nature relies on robust, but powerful, communication with the server. We explain how this technology powers server-side Blazor in the next section.