As men and women may not be alone, please send me Qur’anic and ahadith references that outline the types of friendships non-mahram men and women may have. Mahram describes those who may not marry each other because of their close family ties. What for example, about Internet friendships?

There is no harm in modest friendships. The issue of hijab must be observed, and a man is not permitted to be alone with a woman behind closed doors. The Holy Prophet (PBUH) pointed out in a hadith that if they were alone, Satan would remain alongside them. Internet friendships follow the same rules.