Wikipedia, lol. PR is anything you want it to be for social media.
The Goal of a Press Release
The main purpose of all press releases is to promote something significant and specific, and to do so clearly. Beyond that, a press release is a document that adheres to a strict format and serves three marketing and promotional purposes:
To notify the media about an event in hopes that they will spread the word.
To share something about your business, hoping a reporter will see a story in your press release and write an actual news article about it.
To promote your business' appearance on the internet via blogs, websites, and social networks.
There is a debate about whether that last approach really fits a press release, or if "news release" is the more appropriate term. In any case, social media presents a more direct line to your customers than traditional media outlets.
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