Digital Photography in the general aspect is really broad. As for my experience is concerned, I started out with the camera's manual. That is a good starting point and for my opinion, the very first step for everyone who's new to photography is to know his gear. I find it true, at least for my Nikon DSLR.
First, It teaches you the technicalities of your specific hardware, not just the knowledge about the Manufacturer (e.g. Nikon, Canon, Sony, etc) but the information needed for the specific camera model.
Second, introductions to photography which are generally available online, starts with the technical side of photography: Aperture, Shutter, ISO etc, which it in the manual itself, and it's handy, there are downloadable PDFs of it, which makes it portable without the need for internet connection.
Online videos helps, but just to remind that there are a lot of videos online that are misleading when you're not aware with the technicalities. When you're now equipped with the technical knowledge and have appreciated with, then you can proceed with the artistic side of photography.