question #1 Sahih Muslim 837, Book 6, Hadith 367 : What is the significance of praying two rak’ahs before the obligatory sunset prayer in the mosque?

When we were in Medina, the moment the Mu’adhdhin made the call to the sunset prayer, the people hastened to the pillars of the mosque and prayed two rak’ahs with the result that any stranger coming into the mosque would think that the obligatory prayer had been observed owing to the number who were praying then.