Okay, well I'm 14 and I've been learning/working on HTML, and I was wondering what I should learn next. PHP, xHTML, etc. Difficulty is not an object. Really, I don't mind hard stuff. I'm making a website on godaddy, and whats the best code to do so. I need to make a Forum and just a blog, etc. But, I can always just use my friends Forum. So, yeah. Please comment! Thanks!!!
forum? go ahead and download some open source software. phpbb, punbb and smf are the most popular ones. phpbb is in my opinion the best one (was one of the very first one and has been continously been developeped and improved) vbulletin is commercial and probably the "best" one. but to answer your question. from what you tell probably looking into php and javascript would be the next thing to do. php has been developed for just your needs and really easy. and from there its easy to take the next step into "real" application developing.
Learning php would be a good next step. But if you are trying to build a blog I would recommend using Wordpress. Wordpress is wrote in php so you could also learn some basic php.
The second and maybe more important would be to learn Javascript and a Javascript frameword such as jQuery.
Also you said you know HTML, do you already know css, this would be very important too.
Good luck!
Once you are comfortable building web pages that are static and just display some content, try making the page dynamic. PHP and Javascript make the page come alive -- it can create some interactivity on the page itself, or load some content based on rules you write in the program.
For example, maybe you can load a different image based on what the weather is like today -- you can retrieve weather data from sites like weather.com and noaa.gov. Maybe you can create a handy calculator in Javascript as an exercise.
A lot of web pages are going from "static" to "dynamic".
If you are going along the client/server html track, I'd ramp up on Ruby on Rails and jQuery. It will introduce you to some very useful frameworks and the end to end integration that the best websites need.
There's a MediaWiki engine, quite a popular frogpong in a PHP world. Fast (although it still needs 128+ mb ram VDS solution and a shell access, due to its complex DB update scripts), extensible, written in PHP and has lots of to-do tasks.
OP, have you already learned, what HTML selectors are for? Try XPath, maybe? ..if you need some help/tips in a form of chat, just drop your jabber id for a comment.
Well, my own experience cries out against all other answers. Don't start with PHP!
It so easy to create Spaghetti Code in PHP if you're a young and unexperienced programmer. Choosing another language next might be a bit harder and more frustrating but in the end you trained yourself to write clean and simple code.
And another advice: Don't think about languages. Choose something you're interested in and then look for viable options how to implement your ideas.
There several great and easy to learn frameworks like Django or Ruby on Rails
Well, You are student and if you have any inclination of becoming a programmer or even a web dev, try microsoft. Plus you are studen, given your age, check the link , microsoft is offering a lot of things for 100$. http://www.microsoft.com/web/websitespark/
I know I'm probably going to get down-voted for recommending this language, but it will make you a better programmer.
Scheme - http://racket-lang.org/new-name.html
The documentation base is huge, the user community is rich and friendly, and the new functional programming paradigm will put you miles ahead of other programmers at your age. The learning curve will be quite steep, but I bet you'll have a great time.
The language comes with a web server that you can host on your local machine. You're not going to find any giant software applications built with it, but you'll have the opportunity to learn a new language and tackle the problems yourself (like building your own blog or forum).
Go for Ruby
For web development purposes I would go for Ruby, Python and Javascript - as per priority. Python is more popular, mature and has really good tools.
But then again it depends on the use. Ruby is recommended over Python for web development.
If you want a more comprehensive comparison between Ruby and Python, then this link would help: Ruby vs. Python
You may also find this sort of similar post on stackoverflow useful.