Is It Sunnah to Say Salam When No One Is Home?

Ruling on greeting with a wave of the hand

Ruling on shaking hands with an old woman

Ruling on initiating the salam when speaking on the telephone

Prohibition on shaking hands with paternal uncle’s wife even if she is old

Ruling on male student shaking hands with a female classmate

Ruling on greeting a non-Muslim teacher

Is it permissible to delay returning salaams because of enmity?

If it is not known whether a person is a Muslim or a kaafir, can we say salaam to him?

Can we greet the kuffaar with a greeting other than salam?