technical courses

german mooc's.

Zeal is a free and open-source offline documentation browser for developers. You download docsets for the languages, frameworks, and libraries you use, and Zeal lets you search across all of them at once and jump straight to the symbol, class, or function you need.

Online platform with self-paced courses from universities and organizations, featuring certificates, degree programs, free and paid options, and skill development.

This online learning platform offers over 250,000 courses in subjects like programming, data science, and design. Available in 75+ languages with lifetime access.

Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve.

Achieve code mastery through challenge.

Download and solve practice problems in over 30 different languages. For code newbies and experienced programmers.

Wikiversity is a Wikimedia Foundation project devoted to learning resources, learning projects, and research for use in all levels, types, and styles of education from pre-school to university, including professional training and informal learning.

LeetCode is a platform for learning and improving coding skills with the goal of being fully prepared for programming interviews. Choose problems to solve from categories such as System Design, Algorithms and Database, join code contests and engage in mock interviews.

LearnXinYminutes isn’t a good way to learn your first programming language, but it’s a great way to get your feet wet with your third. It doesn’t explain any of those aforementioned oh-so-important concepts, instead expecting you to come with that knowledge at hand.

Free tutorials and reference manuals with examples for Computer Fundamentals, JSF, C Sharp, Flex, GWT, PL/SQL, Eclipse, JUnit, Pascal, Maven, Scala, Spring, Struts 2, HTML5, ANT, iBATIS, Django, JSP, JAVA, JDBC, AJAX, WAP, SQL, MySQL, C/C++, PERL, PHP, Ruby, Ruby on Rails...