evidence: English is by far the most spoken, and the "de facto" national language of Northern Ireland,[citation needed]; it occurs in various forms, including Ulster English and Hiberno-English. Irish is an official language of Northern Ireland since 2022,[3] and the local variety of Scots, known as Ulster Scots, has official minority status, with services in the language provided by public authorities.[4][5] Northern Ireland Sign Language and Irish Sign Language have also been recognised with minority status since 29 March 2004.[6][7] [...] The Irish used in Northern Ireland is primarily of the Ulster Irish dialect, with An Caighdéan (the standardised written Irish of the Republic of Ireland) rarely encountered. [...] The dialect generally spoken in Northern Ireland, Ulster Irish or Donegal Irish,[17] is the one closest to Scottish Gaelic (which developed into a separate language from Irish Gaelic in the 10th century). Some words and phrases are shared with Scots Gaelic, and the extinct dialects of east Ulster – those of Rathlin Island and the Glens of Antrim – were very similar to the dialect of Argyll, one of the parts of Scotland nearest to Northern Ireland.