The Internet Archive discovers and captures web pages through many different web crawls.
At any given time several distinct crawls are running, some for months, and some every day or longer.
View the web archive through the Wayback Machine.
[This is a fast-access FAQ excerpt.]
In September 1995, Jeff Adams (jeffa@kurz-ai.com) did a search on
"a corpus of about 40 million words of Usenet news articles", and
counted the following forms:
email 19371
e-mail 15359
E-mail 7572
Email 5906
E-MAIL 3659
E-Mail 2986
EMAIL 1269
EMail 521
eMail 303
e-Mail 42
eMAIL 5
and several other forms each rare enough to be probably "just dumb
typos".
Total without hyphen: 27378
Total with hyphen: 29622
Bob Cunningham searched articles posted to alt.usage.english
between mid-May and mid-September 1995, found 604 instances of
"e-mail" and 235 of "email".
A 1995 poll of subscribers to the Copyediting-L mailing list
produced 60 votes for "e-mail" and 24 votes for "email".
In favour of "e-mail", it has been argued that there are
analogous nonce compounds in "e-" (e.g, "e-vote", "e-boyfriend");
that the hyphen is a clue that the word is stressed on the first
syllable; and that email is French for "enamel". In favour of
"email", it has been argued that this is the spelling used in the
Jargon File, and that there has been a general trend away from
hyphenating words once they become established. Many dictionaries
favour "E-mail", which can be justified by analogy with such forms
as "A-bomb", "C-section", and "G-string".
[See more statistics for numbers of people using the
spellings 'e-mail' and 'email'.]