Cybord...Not Android

Original questions: What race, technically, is Android 18? How can she have a child?

Android 18 is a cyborg, as stated by Mirai Trunks (more human like fighters in the original Japanese version) when he returns from the future to help out the Z Fighters for a second time. A cyborg is a human that has robotic parts, such making them 1/2 human and 1/2 android. Android 18 remains a cyborg throughout all of DBZ and DBGT and is never wished into a human by Krillin, contray to popular fan belief. Krillin wishes that the self-destruct devices were removed from Android 18 and Android 17 because Shen Long could not turn them into humans. Cell, Android 17, and Android 18 were the only androids who were not a full "android." Out of all of Dr. Gero's creations, Android 18 and her brother, Android 17, are still part "human" so Cell can absorb them to achieve his Perfect Form. Secondly, Android 18 can have a child because she is 1/2 human, so she had Marron (who is a flood blooded human).

On a side note, before I am asked this, Android 18 is able to learn new attacks and attack power just like the rest of the Z Fighters and her brother.