What should i learn after getting good knowledge of XHTML, CSS, Web Standards, Accessibility,Usability, Information Architecture and Adobe Photoshop?
or
First I want to learn and be focus to learn anyone of these two? Which language would be good to learn first?
You should learn JavaScript because u need only few days to do it. And for php (and mysql of course) it takes few weeks usually.
The difference between JS and PHP is that JS runs on the client side and PHP runs on the server side.
If you are more interested in doing front-end web development then JS and JQuery would be more beneficial. But if you are interested in learning what happens on the back-end then I would suggest learning a language such as PHP, Ruby, Perl or Groovy. Basic database knowledge and SQL will also be useful here.
I would say it depends on what you want to work :
Working server-side (with PHP, for instance) generally means you'll have to learn more than just the one language you're thinking about.
For instance, to develop a web-application, you'll generally need :
In the end, Javascript and PHP are definitly not meant to create the same kind of things : depending on what you want to do, you'll learn one or the other -- or both -- but it all depends on what you want to do ;-)
It depends on what you want to achieve.
If you want to enhance your front-end with scripting, to add more interactive elements or process data on the page, then go with Javascript. If you want to focus primarily on front-end development then this is your best route.
If you want to process things on the server-side, access databases and begin to build full-fledged web applications, then you should have a look at PHP. This may actually be the best route for you to take since you can then go on to learn Javascript and how that can interact with the server asynchronously, to develop more rich web applications.
Both languages will come with their own extended topics to study, such as accessibility's relationship to HTML and design. Javascript will have its own accessibility issues as well as looking into its performance. PHP will have performance considerations, but probably the most important subject would be security. Use of PHP with databases will also require you to learn about SQL and various database engines, so you can pick one that suits your needs.
Javascript, and not just jQuery - though it is the best of the frameworks, it'd be helpful to be familiar with both JS-proper and other frameworks like YUI, prototype, etc.
With JS, you'd have a nice rounded skillset for front-end dev work. You wouldn't be able to function without a team to do the backend - but such is the price that specialists pay.
If, instead, you went the PHP route (and I'll assume you'd also delve into SQL, otherwise it's kind of worthless) - well, you'd be a dime-a-dozen PHP coder that knows HTML and CSS and your lack of experience in both will kill your prospects. There's a lot more to being a backend developer than just PHP and SQL (though some get by amazingly well with nothing more).
Of course, this is all assuming you plan on getting paid for something - if it's just a hobby or scratching an itch, then just do whatever you want. ;)