(Full Story: MongoDB Quick Reference Cards)
SourceMaking — is the best information source on the Web on such software development topics as design patterns, refactoring and UML. A lot of information freely available through the site’s pages, so feel free to use bookmarklet to leave interesting chapters for further reading.
(Full Story: SourceMaking – teaching IT professionals)
Knovel is a Web-based application integrating technical information with analytical and search tools to drive innovation and deliver answers engineers can trust. Engineers worldwide tap our validated content, optimized search, and data analysis tools to find relevant data fast and to analyze, document and incorporate it into their work.
(Link: Knovel – Technical Engineering Reference Information)
You may be interested to know that this document was originally written for internal use in the Operations department at Google. At the time, I was campaigning for the right to use Ruby on internal projects and I felt that a style and usage guide would probably assist in the battle for the language’s acceptance, as the officially sanctioned languages at the time already had one. If nothing else, we’d at least all end up writing code that was easier to maintain.
(Link: The Unofficial Ruby Usage Guide)