I came across an excellent series of articles on a Software Developers Guide to HTTP over on Scott Allens blog, Ode To Code.
The series covers subjects such as Resources, Messages, Connections, Architecture and Security. It’s a good worthwhile course. The links to each part are here :
Part I: Resources
Part II: Messages
Part III: Connections
Part IV: Architecture
Part V: Security
Scott us also a Pluralsight author who has developed some very good courses on web development and general development.