What are Character Strengths?

Christopher Peterson and Martin Seligman, authors of a famous book on positive psychology, “Character Strengths and Virtues: A Handbook and Classification” define character strengths as a recognised subset of personality traits that are morally valued. 

Later on, some researchers also explain that strengths are ways of thinking, feeling, and behaving that come naturally and easily to a person and that enable high functioning and performance.

Peterson and Seligman identify a comprehensive set of Virtues and Character Strengths that have been valued throughout history, across cultures and religions. They identified 6 Virtues and under them, 24 Character Strengths are developed... (watch the video for more) 

References:

Linley, A., & Harrington, S. (2006). Playing to your strengths. Psychologist, 19, 86-89.

Peterson, C., & Seligman, M. E. P. (2004). Character strengths and virtues: A handbook and classification. New York: Oxford University Press and Washington, DC: American Psychological Association.