Harry Potter seen here with an owl.
In the Harry Potter universe, owls are used to carry messages from one place to another.
Owls in the Harry Potter world are similar, but more efficient that carrier pigeons, as their real world counterparts are only able to return to their home and are limited to distance of around 1000 miles.
In symbology, owls usually represent wisdom and knowledge. The Bavarian Illuminati used the owl in its symbols.
(image source unknown)