Katie Couric is joining Yahoo to anchor a news program for the Internet company as it tries to expand its audience and sell more advertising. Monday’s announcement confirms recent published reports that Couric would diversify into online video programming after spending decades in broadcast television as a talk-show host and news anchor. Couric, 56, will continue to host her daytime talk show, “Katie,” on ABC even after she becomes Yahoo’s “global anchor” beginning next year. Financial terms of Couric’s contract with Yahoo weren’t disclosed. The new job at Yahoo Inc. will give Couric an opportunity to report on breaking news events around the world and interview major international figures. “Joining Yahoo offers a tremendous opportunity to reach people all around the world in the way that they’re using and consuming media today,” Couric said in a statement.