In the state of Oregon, ballot measures fall into one of three categories:
Initiative and referendum measures are brought forth to a vote if supporters gather enough qualifying signatures from Oregon voters to place the item on the ballot. In this sense, ballot measures in Oregon provide voters with unique opportunities to change the law. This is called direct democracy. Oregon is one of 24 states in the United States that operates with direct democracy.
Referral ballot measures are those that originate from the state legislature.