Best language to learn for...

[Tree]

Honestly, it all depends on what you want to do. My to go language is Python, which is a scripting language. It has pretty much every utility you might need to make programs for browser based games (such as Gaiaonline and Neopets). However, other languages might be more suitable for hooking into games such as Runescape and other browser based games based on Java, Flash, etc. It really all depends on what your purpose is.

My recommendation: Python and Java.

Agreed with Python, it's easy to pick up and looks nice to boot. For HTTP, TCP, or a majority of networking related programs I will normally always use Python. I suggest if you do choose to go with Python, get the easy_install tool, then from easy_install get pip. Easy_install and Pip are both basically package managers for Python that make installing new packages, modules, etc very easy. For HTTP related things instead of using urllib and urllib2 I tend to use the requests module, which can also be installed from pip. HOWEVER you should still learn how to use urllib and urllib2 in case it's ever needed.
In all honesty you should start with Python 3.3 unless you absolutely need a lower version of python, which in that case I recommend 2.7 as it's easier to transition between the two. It's always been my opinion to just jump right into a programming language you want to learn. The more mistakes you make as you go on the more you learn.