about > help > What Are Hashtags ("#" Symbols)?
A hashtag is similar to other web tags- it helps group tweets by category.
Hashtags are not an official Twitter feature, but rather, are a convention established by users to organize tweets into categories or by keyword. There are many commonly used hashtags.
Twitmart uses hashtags to categorize tweets by "classified ad section" defining a set of standard hashtags.
For more information see help.twitter.com Twitter documentation:
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