O-1 is similar to the H-1b, except limited to those with extraordinary abilities in science, art athletics, education, or business. Visas are limited to 3 years or less and extended in 1 year increments.
The O-3 dependent visa is a nonimmigrant visa which allows the spouse and unmarried children below 21 years of age of O-1 and O-2 visa holders to enter into the U.S. and reside with the family. Those on the O-3 are authorized to study in the U.S., but they cannot receive employment authorization.