Hillary Clinton has described herself as the most famous person you don't really know. And as she launches into her second presidential campaign, she'll be reintroducing herself to voters who largely think they have her figured out. Mel Evans/AP hide caption

Pope Francis (left) is greeted by the head of Armenia's Orthodox Church, Karekin II, in St. Peter's Basilica at the Vatican. The two met during an Armenian-Rite Mass. Gregorio Borgia/AP hide caption

Liz Treston received thousands of dollars from FEMA and the Small Business Administration after Superstorm Sandy destroyed her basement. Two years later, FEMA demanded more than $4,000 of that money back. Alex Welsh for NPR hide caption

This spiral CT image of the chest shows a large malignant mass (purple) in one lung. A conventional chest X-ray could have missed this tumor, radiologists say. Medical Body Scans/Science Source hide caption

Some researchers recommend starting mammogram screening at age 40, while others say age 50. Some doctors think screening should be based on a woman's overall risk for breast cancer, not just her age. Hero Images/Corbis hide caption

British Prime Minister David Cameron delivers a speech on April 12, 2015 in Cheltenham, England. Britain goes to the polls in a general election on May 7. But campaign slogans and speeches — from Cameron and his rivals — won't carry many references to international affairs. WPA Pool/Getty Images hide caption

Last year's champion, Bubba Watson, helps Jordan Spieth put on the iconic green jacket Sunday at the 79th Masters Golf Tournament at Augusta National Golf Club. Jim Watson/AFP/Getty Images hide caption

Students at the Pennsylvania College of Technology are learning a technique called "tripping pipe," moving a pipe from a stack into a horizontal position and lowering it down into a well. The students train on a practice drilling rig to learn how to be roustabouts. Jeff Brady/NPR hide caption

The small town of Wahpeton, N.D., is one of the places where conversations on same-sex marriage are playing out in schools, churches and families. Maggie Penman/NPR hide caption