" مَثْنَى مَثْنَى وَالْوَتْرُ رَكْعَةٌ مِنْ آخِرِ اللَّيْلِ "
It was narrated from Ibn 'Umar that: A man from among the people of the desert asked the Messenger of Allah (ﷺ) about prayer at night. He said:"(It is) two by two, and Witr is one rak'ah at the end of the night."