eBooks - Programming, Development, Architecture, Security, WebOps, IoT Web Development, Data and Business

O'Reilly has a bunch of eBooks they just opened up as free for download in the programming, development, architecture, security, WebOps, IoT Web Development, Data, and Business.

http://www.oreilly.com/programming/free/
http://www.oreilly.com/business/free/
http://www.oreilly.com/data/free/
http://www.oreilly.com/iot/free/
http://www.oreilly.com/security/free/
http://www.oreilly.com/web-platform/free/
http://www.oreilly.com/webops-perf/free