Android
An android was an advanced form of robot, equipped with a self-aware artificial intelligence and made with the purpose to imitate humanoid lifeforms in at least rudimentary physical form.
Androids began replacing other forms of robots in the late 22nd century when it became clear that a more lifelike appearance was needed for successful interactions with Humans. The biggest challenge that androids continually had was their inability to fit seamlessly into society.
Androids were generally used for tasks that humanoids found either dangerous or tedious such as trash collection or cleaning up hazardous materials. Androids were generally many times stronger than the people who built them and therefore are much better able to survive in poor environmental conditions. This ability made them both very useful to their creators but also made them more likely to be destroyed, an issue that Federation ethicists debated for some time.
The first truly successful android in the Federation was the Soong-type android Lieutenant Commander Data of the USS Enterprise-D. His eventual growth beyond his original programming created renewed interest in the field of humanoid robotics.
