If you are thinking of choosing a pet as a Christmas gift, think again. Bring the person to the shelter and let them decide. You may be thinking cat and the future owner might be thinking dog. Above all, it's a very personal choice.
If the pet is for a child, discuss pet responsibility. The most vociferous child begging for a pet must be told that parents can't do all the work required. If the child loses interest and the adults get unwittingly stuck feeding; walking, cleaning litter boxes, etc., it's best the pet be returned to the shelter. A pet cannot be ignored. It can't be thrown aside carelessly like an unwanted toy. It needs care 24/7.
The best age for a child to have a pet is when they can grasp the needs of animal care. The maturity level changes with each child. It's up to the parents to make the right decision. Cat? Dog? Assigning chores. Listing realistic expenses that will occur during the lifetime of the pet. One must think long term.
Upcoming: More tips for the ultimate shelter experience