Ticks and fleas are parasites that live in the hair of your dogs and puppies. Fleas are very small, wingless insects that feed on the blood of dogs (and other pets, mammals and birds).
Fleas are a nuisance, but do not threaten the overall health of your pet in most cases. In extreme cases, fleas can spur allergic outbreaks, hair loss and anemia. If your dog has poor overall health to begin with, a flea infestation can make it worse.
Ticks are larger arachnids that also survive on the blood of dogs, mammals, birds, and also sometimes your amphibian pets. They can deliver havoc to your home.
Ticks are a somewhat more serious problem in your pet's life, because they are known vectors of many different diseases - diseases that are just not welcome in your home.