game development / unity

Unity, Free

The most widely-used game engine in the world, and the one behind a huge share of mobile and indie games. Learn it free on Unity's own platform, then keep the docs close. All resources current.

Unity powers more shipped games than any other engine — especially on mobile — and Unity skills are in constant demand. It uses C# and has a gentle-ish learning curve with an enormous ecosystem of assets and tutorials. Unity Learn is the official free training platform, with guided projects that take you from zero to a finished game. Start there, and use the manual as your reference.