What are some alternatives?
Fandom - Anyone can create a wiki!
LibreOffice - Base - Base, database, database frontend, LibreOffice, ODF, Open Standards, SQL, ODBC
Wikipedia - Wikipedia is a free online encyclopedia, created and edited by volunteers around the world and hosted by the Wikimedia Foundation.
TiddlyWiki - TiddlyWiki — a non-linear personal web notebook
FileMaker Pro - FileMaker Pro Advanced includes all the features of FileMaker Pro plus a set of advanced tools so you can rapidly build powerful custom apps.