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The Oxford English Dictionary says that moon was not originally referring to month in honeymoon. They write that the word means:

The first month after marriage, when there is nothing but tenderness and pleasure’ (Johnson); originally having no reference to the period of a month, but comparing the mutual affection of newly-married persons to the changing moon which is no sooner full than it begins to wane; now, usually, the holiday spent together by a newly-married couple, before settling down at home.

So it is moon because it refers to the phases of the moon, not because it was a period of month. The first attested written use is in 1546:

1546 J. Heywood Prov. (1867) 14 It was yet but hony moone.

The World Wide Words agrees with the OED, and says that the stories about couples eating honey are actually false:

There are many invented stories about the origin of this word, mostly so sickly that I cringe at repeating them. There is, for example, the suggestion that at some time in some place there was a custom for newlyweds to drink a potion containing honey every day for the first month after the nuptials. But the word only turns up in English in the middle of the sixteenth century.

Let me quote you a passage from Richard Huloet’s Abecedarium Anglico Latinum of 1552 (in modernised spelling): “Honeymoon, a term proverbially applied to such as be new married, which will not fall out at the first, but the one loveth the other at the beginning exceedingly, the likelihood of their exceeding love appearing to assuage, the which time the vulgar people call the honey moon”. Putting it simply, it was that charmed period when married love was at first as sweet as honey, but which waned like the moon and in roughly the same period of time.

This comes from military, amateur and CB radio communication

"Do you copy?" or "Copy that!" is likely from when a message had to be written down to be shown to a superior officer

http://en.wikipedia.org/wiki/Voice_procedure

Some words with specialized meanings are used in radio communication throughout the English-speaking world, and in international radio communications, where English is the lingua franca.

Affirmative — Yes
Negative — No
Reading you Five / Loud and clear — I understand what you say 5x5.
Over — I have finished talking and I am listening for your reply. Short for "Over to you."
Out — I have finished talking to you and do not expect a reply.
Clear — I have finished talking to you and will be shutting my radio off.
Roger — Information received/understood.
Copy — Mostly used to acknowledge received information. [May also mean Repeat back to me the information I just gave you. ed.]
Wilco — Will comply (after receiving new directions).
Go ahead or Send your traffic — Send your transmission.
Say again — Please repeat your last message (Repeat is not used as it is a specific command when calling for artillery fire)
Break — Signals a pause during a long transmission to open the channel for other transmissions, especially for allowing any potential emergency traffic to get through.
Break-Break — Signals to all listeners on the frequency, the message to follow is priority.

http://www.dyerlabs.com/communications/procedural_codes.html

Copy probably originally referred to writing or typing a received message, but now has is essentially the same as 'Reading you ...'.