If we collect all the texts of the Ahādīth which mention
Salātu’l-Witr and Salātu’l-Layl, the picture which emerges is the Witr prayer
is actually a part of the Tahajjud prayer, which it seems from the Qur’ān was
obligatory for the Prophet (sws). He used to pray Tahajjud so that the total
number of Rak‘āt would be odd in number. The manner in which he did this was
that he would first pray even number of Rak‘āt and then make them odd by praying
one more Rak‘at and at times three more Rak‘āt. The additional odd Rak‘at (or
Rak‘āt) is called Witr – for the word Witr literally means ‘odd’ in Arabic.
Consequently, Witr is not a separate type of prayer as some people think, and
there is no such thing as praying one Witr.