article An article from a journal or magazine. Required fields:
author, title, journal, year. Optional fields: volume, number, pages,
month, note.
book A book with an explicit publisher. Required fields:
author or editor, title, publisher, year. Optional fields: volume or
number, series, address, edition, month, note.
booklet A work that is
printed and bound, but without a named publisher or sponsoring
institution. Required field: title. Optional fields: author,
howpublished, address, month, year, note.
conference The same as
INPROCEEDINGS, included for Scribe compatibility.
inbook A part of a
book, which may be a chapter (or section or whatever) and/or a range
of pages. Required fields: author or editor, title, chapter and/or
pages, publisher, year. Optional fields: volume or number, series,
type, address, edition, month, note.
incollection A part of a book
having its own title. Required fields: author, title, booktitle,
publisher, year. Optional fields: editor, volume or number, series,
type, chapter, pages, address, edition, month, note.
inproceedings An
article in a conference proceedings. Required fields: author, title,
booktitle, year. Optional fields: editor, volume or number, series,
pages, address, month, organization, publisher, note.
manual Technical
documentation. Required field: title. Optional fields: author,
organization, address, edition, month, year, note.
mastersthesis A
Master’s thesis. Required fields: author, title, school, year.
Optional fields: type, address, month, note.
misc Use this type when
nothing else fits. Required fields: none. Optional fields: author,
title, howpublished, month, year, note.
phdthesis A PhD thesis.
Required fields: author, title, school, year. Optional fields: type,
address, month, note.
proceedings The proceedings of a conference.
Required fields: title, year.
Optional fields: editor, volume or number, series, address, month,
organization, publisher, note.
techreport A report published by a
school or other institution, usually numbered within a series.
Required fields: author, title, institution, year. Optional fields:
type, number, address, month, note.
unpublished A document having an
author and title, but not formally published. Required fields:
author, title, note. Optional fields: month, year.
biblatex
, there are additional standard entries... as well as further styles with custom ones and the possibility of adding your own. This question is a little bit like asking for a list of all possible LaTeX macros...