Colic is unexplained crying (not due to pain or hunger). The bouts of crying usually last 1 to 2 hours and the child acts fine between bouts. Your child usually stops crying when held. The colic starts before 2 weeks of age and usually stops by 3 to 4 months of age.
Colic tends to occur in high-need babies with a sensitive temperament. Colic is not the result of bad parenting, so don't blame yourself. Colic is not caused by too much gas.