🌐EnglishEnglishDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsSvenskaTiếng ViệtРусскийالعربيةفارسی한국어中文日本語EntityQ320357· pop 32· linked from 495 articlesclosed setAlso known as closed subsetset whose complement is an open setAvailable in 32 languagesEspañolFrançaisDeutsch中文日本語РусскийPortuguêsItalianoالعربيةBulgarianCatalanConnectionscontinuous functionEntityHausdorff spaceEntityCategoriesGeneral topology