I recently got into a discussion with a friend who was confused about the difference between emotional support dogs and service dogs. Big difference. Emotional support dogs (as well as other animals) are wonderful companions but they are not recognized by the American with Disabilities Act. They are not trained to perform services specific to a person's disability such as a guide dog for a blind person.
Service animals must be allowed to accompany their handler in public places (some exceptions like zoos) even if the establishment has a "no pets" policy. I am so grateful for these special furry soulmates.