The IMDb was started as a resource of the newsgroup rec.arts.movies, where movie fans would gather to discuss movies and share knowledge. During the time from 1990-1993, it grew as a more or less decentralized, free-for-all system.
In April 1994, the IMDb took another step forward, centralizing the point for submitting information for the growing variety of lists. Prior to this, people wanting to submit information to the database had to find the name and e-mail address of the person(s) who maintained the particular list(s) that applied to the information they wanted to submit, and then had to send it to the appropriate listmanager(s). With the centralized e-mail interface, all the information could be submitted to one place.
In 1998, IMDb was bought by Amazon.com, and with the infusion of this money it grew to become the premier site that we know and love so well, containing accurate and relevant information about hundreds of thousands of movies.