It’s true that you can learn almost anything for free online these days. The trick is knowing where to find the information you need, though. These ten sites will help you get your geek on and learn something new.

1. 5min Tech

From tech news and product reviews to quick tips and tutorials, 5min Tech is the perfect place to get your geek fill in just a few minutes. There’s also a specific DIY section listed in the tech category including simple how-tos and more in-depth hacks.

2. Codecademy

Codecademy offers coding lessons that are not only free, but fun and challenging as well. With new languages being added all the time, the site currently offers lessons in HTML, CSS, JavaScript and Python.

3. Google Code University

For more variety in coding lessons, Google Code University is a great place to look. Available lessons include Android app development, C++, HTML, CSS, JavaScript, Python and Go.

4. Radio Lingua

There are plenty of places to learn a foreign language online, but the tools you can take with you anywhere are often the ones that really make a difference - at least when it comes to regular practice. Radio Lingua’s one-minute language podcast series offers standards like French and German, as well as others like Flemish, Arabic and Zulu. If you have an iPhone, Mindsnacks’ language games are a great addition to any language-learning program.

5. Khan Academy

If math and science are your thing, Khan Academy is where you want to be. This free collection of videos cover topics such as algebra, calculus, biology and chemistry, as well as offering finance, economics and history lessons.

6. Academic Earth

Similar in vein to Khan Academy, Academic Earth offers a wider variety of topics, including computer science, business and design.

7. Let’s Make Robots

Let’s Make Robots is full of advice, discussions, challenges and tutorials for building arguably one of the coolest things in the world. There’s even a beginner’s guide to help you build your very first robot in just two hours.

8. Stack Overflow

One of the best resources available for programmers is Q&A site Stack Overflow. Pretty much any question you have about coding can be answered here.

9. Hack This Site

If you’re an aspiring hacker, Hack This Sitewill help you hone your skills with articles, discussions and challenges.

10. Geekli.st

With the addition of a voting system for shared links on Geekli.st, you can now enjoy and curate the content, Reddit-style. The code-specific communities include Javascript, MySQL, Python, PHP and Ruby on Rails, giving you access to plenty of resources and in-the-know geeks to help you out.

This is a guest post by Corina Mackay

Corina is an inbound marketer and social media maven for Attendly, a white label ticketing and event registration startup. Attendly allows web developers to re-brand the product as their own and mark up the booking fees for ongoing profit sharing. You can follow Attendly on Twitter at @attendly.