Most common cause for nose bleeding is-
Trauma to little's area
A.V. aneurysm
Postero superior part of nasal septum
Hiatus - semilunaris
Little area (also called as Kiesselbach’s plexus) is a highly vascular area in the anteroinferior part of nasal septum just above the vestibule
It is the most common site for nasal bleeding as this area is exposed to the drying effect of inspiratory current and to finger nail trauma.