These policies are widely accepted amongst editors, and are considered a standard to be followed.
Ignoring policy could result in reversion of edits and/or blocking of editing rights.
Except for minor edits, please make use of the discussion page to propose changes to this policy.
You may have arrived at this page via a link on a protected page. A protected page is one which can only be edited by sysops. Users can request a page be protected or unprotected at the request page.
Pages in the MediaWiki namespace are protected by default, for several reasons:
Many messages are in plain HTML, hence users could insert malicious scripts,
Vandalism of some messages would be extremely disruptive, for example changes to the text of the links in the sidebar would immediately be visible to all users,
Navboxes, Amboxes, nesting tricks, and other high-risk templates are protected from vandalism for the same reason.
A few messages can cause the software to stop working if they are changed.
Enforcing a "cool down" period to stop an "edit war," upon request. In such cases, protection is not an endorsement of the current version and any changes to be made should be discussed on the article's talk page.
Protecting a page that has been a recent target of persistent vandalism or persistent edits by a banned user.
Preventing changes to a page while investigating a possible bug.