Twitter provides the world of social media with a channel for short-form self expression. From the tweets you post to those you share through the process of retweeting, you can speak your mind and interact with others' points of view. Twitter's retweets and hashtags provide convenient ways to forward what others say and summarize what you think. When enough Twitter subscribers communicate about the same subject matter, the results gain measurable impact.

Contributing to a Trend

Although most activity on Twitter focuses on interactions between individuals, some of it accumulates into service-wide trends. The list of Trending Topics that appears in the sidebar of your Twitter timeline or profile page includes the subjects that currently captivate a majority of attention. When other people repeat a tweet or focus their conversations around shared subject matter, the volume of conversation surrounding those people or topics can raise them to a point in which they resonate throughout the Twitterverse. Hashtags and retweets provide the means of building momentum and visibility for a person or subject, even if only briefly.

Hashtag Functions

Twitter recommends using no more than two hashtags in an individual tweet. Hashtags summarize a point, reference a concept and provide a shorthand way of referring to an activity, place, event, person or thing. When you use Twitter search to find instances of a hashtag, your results show tweets from across the service. As the volume of hashtag use rises, it can propel a subject into Twitter's Trending Topics. A hashtag consists of the "#" symbol, also called the hash mark or pound sign, followed by a sequence of letters and numbers that spell out or abbreviate a word, name or concept. Spaces and punctuation close off a hashtag sequence. For example, the sequences "#myname is" and "#myname.is" both produce the hashtag "#myname" because of interrupting characters. If you type other characters directly in front of the hashtag marker or try to construct a hashtag entirely out of numbers, your tag won't function.

Retweeting Methods

In Twitter's early days, the retweet developed as a means of repeating what another subscriber said, either out of praise or scorn for an attitude or observation. Typing "RT" and pasting in a copied tweet turned a post into a retweet. This method still works, but the practice proved popular enough that Twitter incorporated it directly into its user interface, placing a "Retweet" link below almost every tweet you see in your timeline. If you follow a user who protects her tweets, making them invisible to anyone except the people she accepts as followers, you can't retweet what she says. If a post you retweet contains a hashtag, your retweet raises the hashtag's popularity.

Other Considerations

Twitter frowns on attempts to misuse its system and features to further a private agenda. You can't retweet a post more than once using the automatic version of the process, but if you attempt to amplify the status of a hashtag artificially through a repeated series of manual retweets, you risk the prospect of account suspension. If you use a third-party utility to automate the process of posting about trending topics, your tweets may disappear from search results.