On a related note: I've had to help train a bunch of Java/C++ devs about web dev over the years. I've also talked to a lot of new devs. One thing I noted is that there wasn't a good resource that tried to explain the key pieces of web dev concepts, terms, and technologies, and how they fit together. So, I ended up writing a "How Web Apps Work" blog series to try to fill that gap:

https://blog.isquaredsoftware.com/series/how-web-apps-work/

The series provides an overview of HTTP and servers, client dev, browsers / HTML / CSS, JS / DOM, and AJAX.

A number of folks have told me they found the series particularly helpful.