By socializing your dog we mean introducing him or her to a variety of objects, people, animals, and environments so that he or she becomes comfortable in a wide range of situations.
There is a great value in your dog already being exposed to a certain situations, since it helps him being calm rather than being worried or unsure around those situations. I have seen dogs who don’t feel comfortable walking on wooden floors, shiny floors, going into the elevator or walking through the garage or facing a vase with flowers-just because they were never exposed to those environments. It is also very important to have your dog meet new dogs who are well behaved to help him develop social skills.
Puppies in their sensitive period (between 3 and 20 weeks) are generally very accepting of new situations. Adult dogs might need more work than that and might progress slower.
It is always very important to associate the new situation with something good the dog values.
Good socialization helps your dog to lead a better and less stressed life!