The letters in Urdu are derived from the Persian/Farsi alphabet, which is derived from the Arabic alphabet. The additional letters that are found in Urdu include ٹ ,ڈ ,ڑ (ṫ, ḋ, ṙ). To make the alphabet more enriched two letters were created for sounds ه (h) and ی (y). By adding these letters to the existing Persian letters the Urdu alphabet became more suitable for the people of Pakistan and North India.