Index of topics
ISNI – International Standard Name Identifier
This is one of the international standards for disambiguating identical names for different individuals. You can contact one of the regional standards bodies and request an ISNI (free). It's intended for all sorts of creatives — writers, musicians, artists, etc. — as well as anyone else in the public eye who needs to be uniquely identifiable, including scientists, living and dead. Einstein has an ISNI number.
You can see at the bottom links to VIAF and the LC (Library of Congress LCCN-N) authority records mentioned in the MARC and LCCN sections above.
ISTC – International Standard Text Code
This is one of the international standards for aggregating all manifestations of a text under a single identifier. For example, I have 4 formats for my book To Carry the Horn — trade paperback, epub, mobi, and streaming audio. That's one text, 4 manifestations. For some sorts of sales analysis, it's useful to be able to lump those things together. That's what the ISTC is used for. You can contact the standards body and request an ISTC for each of your titles (free).
OCLC – Online Computer Library Center
Much of what they carry is described in the MARC section above. Zero in on a typical record and expand all the sections to see the sort of data that they focus on.
Not only do they maintain the bibliographic data about the works in their system and the libraries that hold them but they also maintain or cross-reference to a variety of authority files.
Worldcat even maintains its own summaries by person, using the Library of Congress LCCN-N identifier from the LCCN section above. Handy for seeing a summary of libraries (without the details, alas).