A robot is a cybertronic machine that is built to move around and mimic a living organism. They are usually built in factories and put into market for various different purposes.
Nanobots are microscopic robots that are used for various different purposes including medical, scientific, engineering, manufacturing and so much more.
"Android" is a word used to describe a humanoid robot or a robot built to resemble a specific intelligent lifeform.
A Love Bot is a kind of robot that is built to satify sexual desires.