They were named after the difference engine. Their brain was replaced by a research probe from the future. It gave the Difference Golems their own personality and made them able to move, talk and think like humans. Each golem was slightly different to the others. They appeared in different sizes and shapes. Some had hammers or scissors for hands others had hoppers built into their backs etc. They all looked different.
Joseph Montague wanted to use Difference Golems to liberate humans from slavery and dangerous work. He wanted to change society for the better.
The Difference Golems should replace the human servants. Instead the households should have several mechanical servants. Servant was, according Joseph Montague, just another word for slave.
However, after the Bloody Sunday in 1887, Joseph Montague feared that the Difference Golems would be used as instruments of injustice or terrible men of war. Rather than being servants of the men, they might have turned out guards and soldiers for the few. Joseph Montague shut down his factory and put his first Difference Golem Adam to sleep.
In 2011 Adam was reactivated by Sky Smith. He didn't want to be alone. He went to Joseph Montague's old factory, where Joseph Montague had left the unfinished Difference Golems. Adam let them come to live by putting parts of his mind into the robots, whom he called his children. He soon realised that each time he gave them the spark of life he was diminished by the process. Sometimes he even seemed to forget who he was. Rani Chandra convinced Adam that he couldn't keep up dividing a brain like that. Adam took out the research probe of the brain and gave it to his daughter who promised to bring the probe back to the future. After this Adam's mechanical body was just as liveless as his children. (AUDIO: Children of Steel)