USB, Thunderbolt, Displayport & docks
(via,
also)
is a high density 'overview' of the technology of all of these things,
or at least the technology of the connectors and connections involved.
Since it gets down to the level of the number of lines and lanes (and
their speed) involved in USB signaling and so on, it's an overview
only from a certain perspective.
Although I read it through once and absorbed some things, I think of
it more as a reference work that I can consult for fairly low level
details if and when I need to understand some aspect of the entire
USB mess (and it is a mess) at some depth. There is certainly a lot
there.