Dogs are very social creatures, and they put their remarkable sense of smell to great use. The way they gather information from sniffing is their form of social networking.
If you’re at all familiar with Facebook, it’s not hard to make the connection between your social network and your dog’s community of scents. We typically use Facebook to stay connected with our friends and friends of friends. Dogs connect with other dogs by using their noses. When a dog makes his mark by peeing on something, he leaves a bit of himself behind for other dogs to share—similar to leaving a comment on Facebook.