ERIC Clearinghouse on Handicapped and Gifted Children (1985) quotes three types of characteristics of gifted children: general behavioral, learning and creative characteristics.

General Behavior Characteristics
Gifted children's behavior differs from that of their peers in the following ways:

•  Many gifted children learn to read early, with finer understanding of the language nature. Among from the gifted and talented kids roughly a half has learnt to read before entering school.
•  Gifted children often read a lot, promptly, with enthusiasm and have rich vocabulary.
•  In most cases gifted children learn basic skills better, faster, and need less practice.
•  They have more flair for inventing and managing abstractions.
•  They frequently acquire and take to mean nonverbal signs and can make conclusions that other children need to have explained for them.
•  They try to get at the roots of things, in the hunt for the "how’s" and "why’s."
•  At an earlier age they can work without much help and can concentrate for longer time.
•  Their interests are both amusingly mixed and firmly in-focus.
•  Habitually they have infinite energy, which leads to erroneous diagnosis of hyperactivity now and then.
•  Gifted pupils easily find common language with parents, teachers, and other adults as a rule. They may prefer the fellowship of senior students and adults to that of their age-mates.
•  They like to learn more and more, eager to perceive the strange, and are exceedingly curious.
•  They tackle tasks and problems in an efficient, goal-directed, and well-organized manner.
•  They show an intrinsic motivation to learn, ascertain, or investigate and are often very persistent in their efforts. "I'd rather do it myself" is a prevalent position.