Where we are today is very different. A great deal of the work that was once done on the server has now moved into the client side, and as the complexity of the web UI's grows, the need for individuals with a background in CS that can develop well structured and robust JS applications will grow with it. Couple this with the expansion of mobile development using tools like PhoneGap and Sencha Touch, server side frameworks like Node.js, and the growing shift of desktop applications into "the cloud", it is clear that JS is here to stay. Despite its growing relevance, many professional developers still refuse to embrace it and leave it as something to be dealt with by client side programmers. The problem with this attitude is that web developers are often not well suited for the demands of today's JS applications. Web developers are trained to design appealing and usable interfaces and transfer these designs into accessible HTML/CSS pages, not to write 5000+ line object oriented or functional* applications. What we need are individuals with a strong knowledge of design patterns, data structures, and OO or functional programming to produce code that is maintainable and robust. The best way to make this transition is to start with a framework that removes the drudgery of cross browser compatibility and activates the power of JS. For me this was the outstanding Dojo toolkit which has turned JS programming from a chore to a joy. While the learning curve for Dojo can be a bit steep, it lends itself well to server side developers as it centers around packages, classes, and all the other goodies of OO programming. With a proper toolkit in hand you'll find that JS is not the steaming pile you thought it to be, but rather another valuable programming language to be mastered. Your versatility and value as a programmer will grow, you'll find that developing highly interactive and innovative UI's is both challenging and rewarding, and you'll be well positioned to develop class leading web applications from start to finish.
Note: Although I've focused largely on Dojo in the last part of this post, I'm not saying that you should ignore other toolkits like jQuery. jQuery is a great framework in its own right, but given that I have geared this post towards server side programmers I've chosen Dojo as it's syntactically familiar and heavily object driven, and hence more accessible this group of users.
* A thanks to HN poster gibsonf1 for pointing out my omission of functional programming. Whether you are a server side functional or object oriented programmer is irrelevant. Functional frameworks like backbone.js are great if you have a lot of experience with LISP, Clojure, Haskell or any other functional language. The important thing is to pick a framework that matches your style of server side programming and apply the same rigor towards writing great JS code.
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