A Facebook event is a calendar-based resource which can be used to notify users of upcoming occasions. Events can be created by anyone, and can be open to anyone or private. The creator can invite his friends, members of a group, or fans of a page.
Facebook events are a great way to spread the word on upcoming events or occasions, since they are able to reach thousands of people in a short amount of time. The event also provides an "RSVP" list, which displays lists of invitees grouped by their response. Invitees are either placed in "attending," "not attending," "may be attending," or "hasn't responded" lists. If an invitee RSVPs that the are "attending" the event, it appears in their news feed to notify their friends. When the date of the event approaches, it is displayed on the invitees' home pages to remind them.
Facebook Help Centre explains how to use the events application.
Darrell Etherington discusses the pros and cons of marketing through Facebook events.