It was narrated that Ali, may Allah (SWT) be pleased with him, said: The Messenger of Allah (ﷺ) said: O people of the Qur'an, pray witr, for Allah, the Mighty and Sublime, is Witr (One) and loves Al-Witr (the odd numbered).'
It was narrated that Ali, may Allah (SWT) be pleased with him, said: Witr is not essential like the obligatory prayers, but it is the sunnah of the Messenger of Allah (ﷺ).