[mikekchar]

This is true, however javascript is a tool that can be useful if you are building something that provides an interactive experience for the user.

In such a scenario, I have to write code somewhere to provide the experience. If I am writing it on the server side I run into several issues.

It uses server resources. For example, let's say the user is looking at a large dataset. They want to sort/search/filter that dataset. Given that they already have the data in their client, it often makes sense to use their resources to sort/search/filter the data. This lightens the load on the server.

User actions suffer from latency talking to the server. Again, if the user already has all the data that they want, not talking to the server can often result in a better user experience. Imagine something like an incremental search. Such a thing might even be impossible to implement server side due to latency issues.

Implementing client side functionality in the server can add to software complexity. Things like keeping track of user state can be handled much more cleanly on the client side.

Very often it makes tremendous sense not to make a "web page" for something that needs a lot of user interaction. Instead you want a stand alone application that gets data (without presentation) from a server. Writing your application in javascript, running it in a browser, using HTML as a presentation layer and using HTTP as your communication protocol is not a stupid way of implementing such an application (and I say this having written these kinds of applications with a variety of different technologies).

If you are writing a web page that is intended to simply present data, then Javascript may very well be unnecessary. For me, though, this does not come anywhere close to 90% of my goals.

[smadge]

I don't think client side scripting is always innapropriate. I just think it often is. For example, I've seen a lot of pages that just display some copy marketing a product that won't display properly without JavaScript. On the other hand, complex sites like github work fine without JavaScript.

I totally agree, if you are thinking about maintaining user state on the server, you are probably doing it wrong, as you are violating REST. That's the nice thing about using dumb clients, is it forces you to think about application state changes using hypermedia, instead complex client side logic. I think this leads to clean APIs.