A pastebin is a type of web application where users can store plain text. They are most commonly used to share short source code snippets for code review via Internet Relay Chat. The first pastebin was located at pastebin.com, but other sites with the same functionality have appeared, and several open source pastebin scripts are available. Many pastebins allow commenting, where readers can post feedback directly on the page. GitHub Gists are a type of pastebin with version control.
Pastebins were developed in the late 1990s to facilitate Internet Relay Chat "chatrooms" devoted to computing, where users naturally needed to somehow share large blocks of computer input or output in a line-oriented medium.
On such IRC "channels", where the formatting clues are subtle, and several conversations can be closely interleaved, blocks of computer data nearly always "flood" the queue, even the entire screen, disrupting the intricate flow. Users are warned to use a "pastebin" or risk being "kicked" for "flooding". By using a web link to a pastebin posting, an IRC user can avoid being "banned" for flooding a large block of computer data onto the IRC channel. Instead, a reference to it is a one-liner, and the usual protocol of an IRC conversation.
A new class of IRC bot evolved. In a chatroom that is largely oriented around a few pastebins, nothing more needs to be done after a post at its pastebin; the receiving party awaits a bot to announce the expected posting by the known user.
Unforeseen uses arose for pastebins. Aside from sharing temporary blocks of what is, overall, unrelated computer data, pastebins are not infrequently used to anonymously publish texts online. Also since pastebins are relatively simple to implement, writing a pastebin web-application is regarded as a good exercise for programmers. Representative pastebins now exist for many programming languages including Lisp, PHP, Perl and Python.
Although created in 2002, Pastebin.com only reached 1 million "Active" pastes (not spam or expired pastes) eight years later, in 2010. In February 2010, Pastebin.com was sold by the original owner, Paul Dixon, to Jeroen Vader, a Dutch serial Internet entrepreneur. Only a few weeks after the transfer, Vader had launched a whole new version of the website which he branded V2.0. In early 2011, V3.0 was launched.
By October 2011, the site's active pastes numbers exceeded 10 million. Less than a year later, in July 2012, the owners of Pastebin.com tweeted that they had already surpassed the 20 million active pastes mark. On June 9, 2015, they announced they had reached 65 million active pastes. They also mentioned that around 75% of pastes are either unlisted or private.
In 2015 Pastebin.com reached 95 million active pastes, and more than 2 million members. 
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