extensible mail transport protocol

mail agent

mail agent software

mail transport non-repudiation

simple mail transport protocol

Chemical Transport Agent

data transport agent

freight transport agent

transport agent

Electric Mail (E-mail)

Electronic Mail (E-mail)

electronic mail， E-mail

E-mail (Electronic Mail)

E-MAIL Electrical-Mail

e-mail， electronic mail

E-Mail， Electronic-Mail

V e-mail Voice E – mail

V-mail video-mail

Separation of Passenger Transport from Freight Transport