|Whether the outer perimeter of something is fenced.|
|JA:Automated Edits code of conduct による承認なしに、データベース内にあるこのタグを別なタグに自動的（または半自動的）に置き換えるべきではありません。 そのような編集は取り消されます。|
Once upon a time there were no barrier tags, because nobody had invented them yet. In that time the only way to map a fence in Openstreetmap was with fenced=yes. Almost all fences mapped since the invention of barrier=fence are (re)mapped using that new tag.
The reason this page still exists is, to let people finding objects tagged with fenced=yes know what it means.
So for general information on how to map fences and associated features please see barriers.
This tag is not rendered by the main Openstreetmap renderers.