This documentation covers all the topics, terminologies, and concepts related to assembly language, independent of its targeted architecture, variant, or ISA. Every question occurring while you read the docs will be covered in one of the units where the explanation will be understandable.
Every unit has an extras.md for topics that are too unrelated to assembly and are just for learner interest.
In this documentation, I have not discussed anything specific to a single architecture. Every detail is written from a completely architecture-independent point of view and presented as a standard perspective. In addition, all examples, including assembly, use Intel syntax.
For the complete project roadmap and upcoming units, see Documentation Unit Structures.