The Keywords field can be used for finding invitations with matching terms in an invite's name, description, location or city fields. The other search criteria can be used to search for invitations by purpose, activity type, location, time, or any combination of the foregoing. Of course, using both keywords and one or more of the other search criteria will enable you to narrow down your results quickly.
You can find events near you by entering in either your city and state or your zip code and selecting a radius within which to search.
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