Nano was a male Lirin who, in his civilization's custom, was generated for one purpose in life: in Nano's case, as an emissary to the Federation, which he fulfilled by being the only of his kind to become a Starfleet officer. In the 2250s, he served as a communications officer aboard the USS Enterprise under the command of Captain Christopher Pike. Like all members of his race, Nano was a skilled pyrotechnic, able to mentally generate fires. Nano himself was classified as a "grade two pyrotechnic".
The Lirin culture has a delicately balanced finite population where everyone serves a specific function. After making contact with the Federation in 2225, the Lirin generated Nano to serve as their emissary to the Federation. This meant Nano could never return home, as he would disrupt the balance.