The 1800s was a time of great inventions, including the light bulb by Thomas Alva Edison, an electric train lamp by Lewis Latimer, and the telephone by Alexander Graham Bell.

The two leading industries at the time were steel making and oil production. Andrew Carnegie started new steel mills, and John D. Rockefeller went into oil refineries. Large businesses, or corporations, were developed. Some corporations had complete control of entire industries.

Immigrants worked in many of the factories of these new industries. They worked long hours under dangerous health conditions and were paid low wages. In 1911 the Triangle Shirtwaist factory in New York burned, and 146 women and girls were trapped in the sweatshop and died. To fight for better working conditions, workers began to organize into groups called labor unions. Samuel Gompers founded the American Federation of Labor, which helped to get labor laws passed that ended child labor, shortened work hours, and made employers pay for injuries on the job.