Slashtags are a set of short community-created conventions for attributing information on Twitter, also called microsyntax. They are designed to be succinct and provide an easy way to provide metadata about a tweet, especially when "retweeting".
Slashtags were introduced by Chris Messina and given their moniker by Chris Blow.
A slashtag is preceded by the "/" character (called a slasher). It is stated that after the initial slash, the slasher is not required for subsequent slashtags. Slashtags normally appear at the end of a tweet.
These are example tweets with fictitious Twitter usernames to show how to use Slashtags.