Reblogging

Reblogging (or, in Twitter parlance, retweeting) is the mechanism in blogging which allows users to repost the content of another user's post with an indication that the source of the post is another user.

It was first developed by Jonah Peretti at Eyebeam Art and Technology Center's R&D program under the project 'Reblog' (from where the term originates) as an open-source tool for individually-run blogs. Tumblr then built it into their social network for re-sharing posts within the network, and similar features ("Retweet" on Twitter, "Share" on Facebook) then followed.

For a number of microblogging and social networking services, reblogging has become a means of both social bookmarking and user commentary; unlike social news services like Digg, Slashdot, and Reddit, however, reblogging typically does not involve a centralized "front page" to which the highest-ranked post is appended.

Reblogging (and the increased attention paid to the indexing and encouragement of reblogging) has become a major feature of many social networking sites and content-hosting services, and it has also become a potent means of secondary content promotion and audience measurement whereby links to external content are syndicated across multiple profiles and the reposts are indexed as a measurement of currency and relevance.

A historical precedent to reblogging is the viral nature of e-mail, as "Internet petitions" and "chain e-mails" which encouraged e-mail users to "resend" the e-mail to at least a minimum number of contacts on one's contact list were highly popular (and highly controversial) in the 1980s and 1990s. With the rise of the World Wide Web, it was not uncommon for webmasters, including major news service websites, to encourage readers of a post to share a link to the post with others on one's contact list. Only in the mid-2000s was the "share via e-mail" solicitation accompanied or replaced by branded "sharing" buttons from various social news or bookmarking services at the time, giving bloggers and news services a seemingly more accurate metric for readership and traffic than ever before; the issue of user moderation, however, gave bloggers and news services pause due to both real and alleged competition in moderation ranking of shared "front-page" posts. With the rise of micro-blogging in the latter 2000s, however, user moderation on front pages was de-emphasized as a feature in favor of "reblogs" on user profiles, which were usually taken by bloggers and news services as automatic endorsement of an original/linked post's currency, if not popular favor.

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Wikipedia