O’Reilly Open Books – Computer and technology related open books from O’Reilly – books with various forms of “open” copyright – over the years.
Free Programming Books – A comprehensive list of freely available programming related Ebooks categorized by Technology/Programming Language
Software Program Managers Network GuideBooks – Books to identify proven industry and government software best practices and convey these practices to managers of large-scale DoD system acquisition programs
MIT OpenCourseWare – MIT(Massachusetts Institute of Technology) OpenCourseWare is a free publication of MIT course materials that reflects almost all the undergraduate and graduate subjects taught at MIT. Check the list of courseware.
CheatSheets – A selection of free, printable quick references for a variety of languages and web technologies
Note: It is very likely that I missed some other resources containing free programming and technology books. Please share them via the comments section and I will add them to the list. Please do not share links of sites contains pirated books. The links will be immediately deleted.