单选题
In 1826, a Frenchman named Niepce needed pictures for his business. But he was not a good artist. So he invented a very simple camera(照相). He put it in a window of his house and took a picture of his garden. That was the first photo.
The next important date in the history of photography(摄影术) was in 1837. That year, Daguerre, another Frenchman, took a picture of his reading room. He used a new kind of camera in a different way. In his picture you could see everything very clearly, even the smallest thing. This kind of photo was called a Daguerretype.
Soon, other people began to use Daguerre's way. Travelers brought back wonderful photos from all around the world. People took pictures of famous buildings, cities and mountains.
In about 1840, the process was improved. Then photographers could take pictures of people and moving things. That was not simple. The photographers had to carry lots of films and processing equipment. But this did not stop the photographers, especially in the United States. After the 1840s, daguerreotype artists were popular in most cities.