In ASP.NET SignalR is a library which is used by ASP.NET developers which is help to adding real-time web functionality into applications. The Real-time web functionality is responsible to send code content to connected clients which are available without having the server wait for a client to request new data. SignalR API is used for creating server-to-client remote procedure calls (RPC) which is responsible to call JavaScript functions in client browsers on other client platforms from server-side .NET code. SignalR also includes API connection such as management instance, connect and disconnect events, and grouping connections. SignalR used for to add any sorted Real-Time web functionality in ASP.NET applications. In chat application Any time a user refreshes a web page to see new data, or the page implements long polling to retrieve new data which using for SignalR. For real Examples likes dashboards and monitoring applications, collaborative applications , job progress updates, and real-time forms.