This category contains pages which have been semi-protected to prevent vandalism and other unconstructive editing. This is done when a page has been repeatedly vandalized by many users, or when such vandalism is anticipated. (Vandalism by a small number of users is more easily dealt with by blocking the users responsible.) This protection is usually temporary, although pages that are vandalized very frequently, such as Wikipedia, are indefinitely semi-protected. Semi-protection prevents a page being edited by anonymous and newly registered users. To edit these pages, users must have been on Wikipedia for at least 4 days and must have made a total of 10 edits to mainstream articles. Very visible pages such as the Main Page are fully protected, which allows only administrators to edit them; see Category:Wikipedia pages protected against vandalism for pages which have been protected for this reason. Use {{pp-vandalism}} or {{pp|vandalism}} to add a page to this category. This should only be done if the page is in fact semi-protected – adding the template does not in itself protect the page.