tell and say

[insatia]

what is the difference in these two words in terms of meaning or grammar?
which one to use here: say no or tell no? say one's name or tell one's name. we use tell a secret instead of say why is that? thanks a lot.

[Anglika]

I wuold suggest that you tell someone something and that you say something to anyone/everyone.

Tell X your name - specifically to an individual

Say your name - generally, perhaps to make sure your name is understood.

He told me a secret - secrets are usually only told to people, otherwise they aren't secret.

[BobK]

(Note also that the more common collocation with 'name' is 'give' - which avoids the problem : 'He telephoned the poice, but refused to give his name.')

b