I haven't programmed web applications so far, so I don't know too much about them. I need to create an application that will be hosted on a server. The user will interact with it via a web page, but I need to make parts of the code to run on the client computer, not on the server.
More precisely, my application will perform some math calculations that could take some time to complete, but I want multiple users to access my app, so it's not a good idea to make it run on the server.
Unfortunately, I don't know which programming language I should learn. I heard that PHP runs the code directly on the server. Does ASP .NET do the same thing? Should I write the code in Java?
Thank you in advance,