Wikipedia:Orphan
An orphaned page is a Wikipedia page with no links from other pages in the main article namespace.
If you think an article is orphaned, add {{orphan|date=April 2024}} to the top of it.
However, because Simple Wikipedia does not have many articles, a large number of them will be orphaned. Because of this, editors are generally encouraged not to tag an article unless it has no incoming links at all from other articles. In other words, as long as there is one other article which links to it, the article should not be tagged as orphaned.
When an article is tagged with {{orphan}} it is added to Category:Orphaned articles. When the tag is removed it is removed from this category. The tag only shows up during the month in which it was added, but remains in the category until it is removed from the article.
To check if an page is an orphan click on What links here in the left panel of the page.