Citizen journalism (also known as participatory journalism, democratic journalism, guerrilla journalism or street journalism) is based upon public citizens "playing an active role in the process of collecting, reporting, analyzing, and disseminating news and information." Similarly, Courtney C. Radsch defines citizen journalism "as an alternative and activist form of news gathering and reporting that functions outside mainstream media institutions, often as a response to shortcomings in the professional journalistic field, that uses similar journalistic practices but is driven by different objectives and ideals and relies on alternative sources of legitimacy than traditional or mainstream journalism". Jay Rosen offers a simpler definition: "When the people formerly known as the audience employ the press tools they have in their possession to inform one another." The underlying principle of citizen journalism is that ordinary people, not professional journalists, can be the main creators and distributors or news. Citizen journalism should not be confused with: community journalism or civic journalism, both of which are practiced by professional journalists; collaborative journalism, which is the practice of professional and non-professional journalists working together; and social journalism, which denotes a digital publication with a hybrid of professional and non-professional journalism.