We currently have two tags on Meta Stack Exchange about sharing:
sharing (79 questions)
For questions relating to sharing a post or promoting the site via email, on Facebook, or on Twitter.
share-this (55 questions)
For questions about any of the sharing options available on the sites.
While an argument could be made that sharing is about the process of sharing a post, and share-this is about the functionality, this distinction is not always made in practice and I'm not sure it's useful either. Should the tags be merged/synonymized (making sharing the master tag)?