What are coping skills?

Coping skills are "An adaptation to environmental stress that is based on conscious or unconscious choice and that enhances control over behavior or gives psychological comfort" (Child Counseling in Davidson). 

Basically, they are any healthy habit that helps to eliminate stress from one's life! There are various types of coping skills and every person will have different ones that work best for them. There is no "one size fits all" coping mechanism.