It's well known that computer applications use old-fashioned terminology, presumably (originally) to make the transition from analogue to digital a less painful one. Copy, cut, paste and print all come from old terms for page layout; Adobe Photoshop uses terms familiar to photographers from the days of the darkroom, such as burn and dodge; folders, clipboards and tabs come from the pre-computer office.
Email, too, is obviously based on the old-fashioned letter, where one composes a letter then posts it (and cc (carbon copy) and bcc (blind carbon copy) come from the old days of the manual typewriter). The old-fashioned letter was either sent or posted, but emails nowadays, in the office environment anyway, are never merely sent: they are dropped, fired or shot, inferring that the busy senders do not have time to merely send an email, but rather employ a far quicker (and violent) method. It does, however, take the same amount of time to send an email as to fire one (both methods are still sent via the 'Send' button, though I'm surprised programmers haven't introduced a 'Fire' or 'Shoot' button into the email interface, just to please those really busy and important people at work).
Though emails are often written in an informal manner, certain conventions have emerged. 'Hi' instead of 'Dear' sets the informal tone, with 'Many thanks' or 'Kind regards' as the sign off, instead of 'Yours sincerely' (for 'Dear Mr/Mrs [Name]') or 'Yours faithfully' (for 'Dear Sir/Madam') in the formal letter.
But when first emailing someone, and then continuing to do so (in a work situation, say), how long should these 'Hi' and 'Kind regards' conventions be retained for? What I mean is, as a recent example with a new colleague, for the first few emails I kept to the 'Hi [their name]' and 'Kind regards [my name]' routine, but is it necessary to carry on after twenty emails throughout the day, when I had got sufficiently e-quainted with the recipient? I believed no, and dropped it. The recipient – shall we call her Kate? – did not drop it, and over the course of a fortnight, persistently emailed me 'Hi [my name]' and signed off 'Kind regards, Kate', even though we had emailed each other dozens of times. Whether these were automated or hand-typed each time is only partly the point: aside from a waste of time and space, they kept the relationship on a purely formal basis.
I was also 'e-introduced' (his words) to someone recently. Has there ever been a more awkward e-word? Those two vowels together just do not, well, go together. Entroducted would sound better, which made me think of of DJ Shadow's 1991 album Endtroducing… which I always thought was spelt Entroducing… (as it was his first album). It took me twenty years (and writing this post) to actually read the title properly.
Finally, someone at work actually picked up on this, after overhearing a phone call. When people give their email address to someone, they usually say 'all one word' (such as 'my email address is email@example.com, all one word') but email addresses are always one word, so there's no need to say it. If there's a full-stop or dash in-between, you'd mention this, sure, but it's still just one word.