Augmented Reality

Today, surgeons, architects and others use AR in their professional lives to enhance their skills and the outcomes of their work.

For the past two years, one of the hottest games on smartphones has been Pokémon Go. Players walk the streets like zombies, staring at their phones and hunting for collectible characters. But what are they actually looking at?

The world, for starters. Streets, parks, houses and public buildings. The game is tied to real-world landmarks, and the most popular sites have true historic significance.

One man in Massachusetts has been surprised by the number of people who have congregated on his sidewalk and pulled up to his address at odd hours. His home was once a gable-roofed church, but is now a Pokémon destination. "Living in an old church means many things," he wrote on Twitter. "Today it means ... Pokémon Go."

His house is real, but the Charmanders and Squirtles around it are not. They are Pokémon characters, exotic cartoons who seem to be living in and around churches, houses and other places in the real world. From parks in San Francisco to the White House...