Project content is written , edited , and posted by independent volunteer contributors who are responsible for their work . In July 2008 , History Commons project manager Michael Tuck wrote in an article for Nieman Watchdog , " Contributors own their content ; the Commons provides a searchable information base where disparate material can be brought together in a single repository . " Like Wikipedia , the History Commons is a database that the public can edit and add content to . Some important differences are that the ability to do so is limited to registered users , and that entries/edits go through an editorial peer-review process before being published . According to a History Commons " Conceptual Summary " , There are three steps to the review process . After an entry is submitted , it is reviewed for content to ensure that it is well-written and well-sourced . Sources are checked to ensure that what is in the entry accurately reflects the source material without resorting to plagiarism . An entry approved for content is then submitted for copyediting , using the HC style manual as a guide . If the event is rejected during the first step , it is sent back to the user , who reads over the comments and then resubmits the entry . If it is approved , another user , who is in charge of managing the user-defined timeline that the event was submitted to , then makes a decision whether or not the verified event should be added to the timeline . Each event is thoroughly reviewed for accuracy and proper grammar and spelling . The " Timelines " page lists the projects that have been published ; there are 32 as of June 2012 . These include projects on the current global economic crisis , the US wars in Afghanistan and Iraq , US prisoner abuse and torture , the loss of US civil liberties , the September 11 attacks , domestic propaganda in America , global warming , US health care issues , US electoral politics , Kosovar Albanian self-determination , and many others
September 11 attacks
September 11 attacks
History Commons