National Pet Day Today, Animal Lovers Celebrate

(PHOTO: REUTERS/Natalie Behring)Winter, a Norwegian Forest Cat, licks turkey-flavored baby food off a spoon as a reward for good behavior at the "Meet the Breeds" exhibition in New York October 17, 2009. The exhibition featured about 200 breeds of dogs and cats.

National Pet Day is dominating social media websites on Friday, with people across the U.S. celebrating their beloved four-legged friends.

The national holiday arrives each year on April 11 and marks an occasion to honor pets of all shapes and sizes, from slimy to furry. Furthermore, National Pet Day encourages people to adopt an animal in need this year. Pets provide countless households with loyal companions who are lovable and fun, and there is a large number of animals that need rescue and adoption.

Data released by the Humane Society of the U.S. reveals that National Pet Day may be working- a survey indicated that pet ownership in the U.S. has more than tripled from the 1970s. According to the HSUS website, 62 percent of American households included at least one pet in 2012.

It may be no coincidence that National Pet Day arrives just one day after National Sibling Day, since pets can provide a special relationship comparable to that found among brothers and sisters. National Pet Day is also reminiscent of holidays such as National Dog Day, National Cat Day, and Kids & Pets Day, which each promote animal adoption as well.

On Friday, thousands of pet owners are sharing their National Pet Day celebrations; from honoring their pets with special treats and long walks to simply showing them extra love. Among those celebrating National Pet Day is Oprah Winfrey. The television mogul posted a video to Instagram featuring her numerous dogs flocked around her.

"National Pet Day… Every doggy gets a treeeeeat," Winfrey captioned the photo.

One Twitter user Carly posted, "It's National Pet Day, so here is a picture of my furry babies. They will be going to the dog park today."

Mathieu added, "Apparently today is National Pet Day. Isn't that every day? Regardless, be extra nice to your fur babies!"

Meanwhile, April 11 is also National Submarine Day and National Cheese Fondue Day.