what's the difference between by and with in terms of means?

[keannu]

I know in the below "by" is more suitable than "with", but with is also used as means, so what is the criteria to choose between the two for means?

ex)They communicate with each other by(with) email.

 

[Barb_D]

Not much difference. You can add "through" to the mix. Or even "via."

Use the one that sounds better to you.