Mail
The mail was a system for physically transporting postcards, letters, and parcels delivered to a particular address or person.

In 2377, while Tuvok said to Harry Kim that he received a letter from someone named Dennis Kim, his cousin from Earth, who spoke of his mutual friend Maxwell Soroyan, Kim asked if Tuvok read his mail, and Tuvok said "yes". ()

Also in 2377, when Tom Paris asked where his mail was, Harry Kim explained everything and Paris said that they couldn't go another month without mail. ()

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Communications technology