Vanishing are the days when readers' contributions to the papers they read are limited to the 'letters to the editor' section. The latest publication to open its arms to reader contributions — in the form of videos, photos and stories — is The Guardian, which launched Tuesday a program called "Guardian Witness."

Guardian Witness, available online, and as an app for iPhone and Android devices, asks users to supply staff journalists with videos, photos and stories for both breaking news events and less pressing features, which could then appear on The Guardian's website and/or in print. Under an Assignments tab, there are calls for photos of tall buildings, essays on how UK government cuts have impacted readers' lives, and accounts from refugees and aid workers in Syria. Visitors can upload their own contributions and view the submissions of others.

Beyond the calls for submissions, Guardian Witness also promises to provide tutorials on shooting video, and asks visitors to send ideas for stories or assignments not already listed.

The initiative is similar to that of CNN iReport and ProPublica's Get Involved, which ask readers to contribute stories and footage for specific assignments, as well as ideas for coverage. For The Guardian, it's a move towards open journalism, as defined by editor-in-chief Alan Rusbridger (below); the more cynical among us might call it unpaid content.

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