Although press release distribution is main focus here, let’s dive first into what a press release should be. A press release is a document that is sent to members of the press—more commonly known as media these days to include newspapers, television, radio, Internet news sites, etc.—to alert them of news or other information that may be of interest to their readers, viewers or listeners.

The media outlet editors then decide whether to include the news item in their publication or broadcast… or ignore it.
If accepted for inclusion, the editors may publish the press release as submitted by the sender, may edit to meet their editorial guidelines, or may even assign it to their staff of writers and reporters to cover or expand on the story.

When a press release, or the content of the release, is accepted and included in a publication or broadcast, it is a win for the person or company who sent the release.
This is often considered earned media since, other than the cost of preparing and sending the release, the sender incurs no cost to receive link or press which means the privilege of being published or broadcast by the media channel. By contrast, advertising is considered paid media since the sender (advertiser) is paying to have their information (ad or story) included.