This article is from the Whippet Breed FAQ, written by firstname.lastname@example.org (Nancy Bennett).
Whippets are generally very quiet and gentle dogs in the house,
content to spend much of the day sleeping on the couch! They are not
generally aggressive with other animals, and although especially
attached to their owners, they are friendly to visitors. They are not
prone to snapping, so they are good with young children. They may or
may not bark when strangers arrive, and are not suited to be guard
dogs due to their trusting and unsuspicious nature. Outside, however,
particularly when they are racing or lure coursing, they demonstrate
their superb athletic skills and will pursue their "quarry" (even
when it is an artificial lure) with the heart of a lion. To see these
dogs in full stride is breathtaking!