One of the advantages of Twitter is that it, like most social media sites, can be easily be used as a free marketing tool for libraries
Libraries can use Twitter to promote their collections to the students and library patrons. (Baker)
A great example of this is using archival collections to post interesting content. Librarians can take pictures of the libraries or campus to post on Twitter for trends like #ThrowbackThursday, which is a popular hashtag among Twitter users for sharing old photos
Libraries can also promote their events using Twitter by using hashtags to create a conversation about the event.
For example, the University of Wisconsin-Madison (along with many other libraries) participated in the recent “blind date with a book” trend. Patrons could pick up books with bags over the physical copy, so they don’t know the title or cover of the book they are checking out. Patrons could take about their “date” using #BlindDateWithaBook, a hashtag that many libraries who do the event use.