-@code{nnfolder-directory}. This only works if you use long file names,
-though.
-
-@node Comparing Mail Backends
-@subsubsection Comparing Mail Backends
-
-First, just for terminology, the @dfn{backend} is the common word for a
-low-level access method---a transport, if you will, by which something
-is acquired. The sense is that one's mail has to come from somewhere,
-and so selection of a suitable backend is required in order to get that
-mail within spitting distance of Gnus.
-
-The same concept exists for Usenet itself: Though access to articles is
-typically done by @sc{nntp} these days, once upon a midnight dreary, everyone
-in the world got at Usenet by running a reader on the machine where the
-articles lay (the machine which today we call an @sc{nntp} server), and
-access was by the reader stepping into the articles' directory spool
-area directly. One can still select between either the @code{nntp} or
-@code{nnspool} backends, to select between these methods, if one happens
-actually to live on the server (or can see its spool directly, anyway,
-via NFS).
-
-The goal in selecting a mail backend is to pick one which
-simultaneously represents a suitable way of dealing with the original
-format plus leaving mail in a form that is convenient to use in the
-future. Here are some high and low points on each:
-
-@table @code
-@item nnmbox
-
-UNIX systems have historically had a single, very common, and well-
-defined format. All messages arrive in a single @dfn{spool file}, and
-they are delineated by a line whose regular expression matches
-@samp{^From_}. (My notational use of @samp{_} is to indicate a space,
-to make it clear in this instance that this is not the RFC-specified
-@samp{From:} header.) Because Emacs and therefore Gnus emanate
-historically from the Unix environment, it is simplest if one does not
-mess a great deal with the original mailbox format, so if one chooses
-this backend, Gnus' primary activity in getting mail from the real spool
-area to Gnus' preferred directory is simply to copy it, with no
-(appreciable) format change in the process. It is the ``dumbest'' way
-to move mail into availability in the Gnus environment. This makes it
-fast to move into place, but slow to parse, when Gnus has to look at
-what's where.
-
-@item nnbabyl
-
-Once upon a time, there was the DEC-10 and DEC-20, running operating
-systems called TOPS and related things, and the usual (only?) mail
-reading environment was a thing called Babyl. I don't know what format
-was used for mail landing on the system, but Babyl had its own internal
-format to which mail was converted, primarily involving creating a
-spool-file-like entity with a scheme for inserting Babyl-specific
-headers and status bits above the top of each message in the file.
-RMAIL was Emacs' first mail reader, it was written by Richard Stallman,
-and Stallman came out of that TOPS/Babyl environment, so he wrote RMAIL
-to understand the mail files folks already had in existence. Gnus (and
-VM, for that matter) continue to support this format because it's
-perceived as having some good qualities in those mailer-specific
-headers/status bits stuff. RMAIL itself still exists as well, of
-course, and is still maintained by Stallman.
-
-Both of the above forms leave your mail in a single file on your
-filesystem, and they must parse that entire file each time you take a
-look at your mail.
-
-@item nnml
-
-@code{nnml} is the backend which smells the most as though you were
-actually operating with an @code{nnspool}-accessed Usenet system. (In
-fact, I believe @code{nnml} actually derived from @code{nnspool} code,
-lo these years ago.) One's mail is taken from the original spool file,
-and is then cut up into individual message files, 1:1. It maintains a
-Usenet-style active file (analogous to what one finds in an INN- or
-CNews-based news system in (for instance) @file{/var/lib/news/active},
-or what is returned via the @samp{NNTP LIST} verb) and also creates
-@dfn{overview} files for efficient group entry, as has been defined for
-@sc{nntp} servers for some years now. It is slower in mail-splitting,
-due to the creation of lots of files, updates to the @code{nnml} active
-file, and additions to overview files on a per-message basis, but it is
-extremely fast on access because of what amounts to the indexing support
-provided by the active file and overviews.
-
-@code{nnml} costs @dfn{inodes} in a big way; that is, it soaks up the
-resource which defines available places in the filesystem to put new
-files. Sysadmins take a dim view of heavy inode occupation within
-tight, shared filesystems. But if you live on a personal machine where
-the filesystem is your own and space is not at a premium, @code{nnml}
-wins big.
-
-It is also problematic using this backend if you are living in a
-FAT16-based Windows world, since much space will be wasted on all these
-tiny files.
-
-@item nnmh
-
-The Rand MH mail-reading system has been around UNIX systems for a very
-long time; it operates by splitting one's spool file of messages into
-individual files, but with little or no indexing support -- @code{nnmh}
-is considered to be semantically equivalent to ``@code{nnml} without
-active file or overviews''. This is arguably the worst choice, because
-one gets the slowness of individual file creation married to the
-slowness of access parsing when learning what's new in one's groups.
-
-@item nnfolder
-
-Basically the effect of @code{nnfolder} is @code{nnmbox} (the first
-method described above) on a per-group basis. That is, @code{nnmbox}
-itself puts *all* one's mail in one file; @code{nnfolder} provides a
-little bit of optimization to this so that each of one's mail groups has
-a Unix mail box file. It's faster than @code{nnmbox} because each group
-can be parsed separately, and still provides the simple Unix mail box
-format requiring minimal effort in moving the mail around. In addition,
-it maintains an ``active'' file making it much faster for Gnus to figure
-out how many messages there are in each separate group.
-
-If you have groups that are expected to have a massive amount of
-messages, @code{nnfolder} is not the best choice, but if you receive
-only a moderate amount of mail, @code{nnfolder} is probably the most
-friendly mail backend all over.
-
-@end table
-
-
-@node Browsing the Web
-@section Browsing the Web
-@cindex web
-@cindex browsing the web
-@cindex www
-@cindex http
-
-Web-based discussion forums are getting more and more popular. On many
-subjects, the web-based forums have become the most important forums,
-eclipsing the importance of mailing lists and news groups. The reason
-is easy to understand---they are friendly to new users; you just point
-and click, and there's the discussion. With mailing lists, you have to
-go through a cumbersome subscription procedure, and most people don't
-even know what a news group is.
-
-The problem with this scenario is that web browsers are not very good at
-being newsreaders. They do not keep track of what articles you've read;
-they do not allow you to score on subjects you're interested in; they do
-not allow off-line browsing; they require you to click around and drive
-you mad in the end.
-
-So---if web browsers suck at reading discussion forums, why not use Gnus
-to do it instead?
-
-Gnus has been getting a bit of a collection of backends for providing
-interfaces to these sources.
-
-@menu
-* Web Searches:: Creating groups from articles that match a string.
-* Slashdot:: Reading the Slashdot comments.
-* Ultimate:: The Ultimate Bulletin Board systems.
-* Web Archive:: Reading mailing list archived on web.
-@end menu
-
-The main caveat with all these web sources is that they probably won't
-work for a very long time. Gleaning information from the @sc{html} data
-is guesswork at best, and when the layout is altered, the Gnus backend
-will fail. If you have reasonably new versions of these backends,
-though, you should be ok.
-
-One thing all these Web methods have in common is that the Web sources
-are often down, unavailable or just plain too slow to be fun. In those
-cases, it makes a lot of sense to let the Gnus Agent (@pxref{Gnus
-Unplugged}) handle downloading articles, and then you can read them at
-leisure from your local disk. No more World Wide Wait for you.
-
-
-@node Web Searches
-@subsection Web Searches
-@cindex nnweb
-@cindex DejaNews
-@cindex Alta Vista
-@cindex InReference
-@cindex Usenet searches
-@cindex searching the Usenet
-
-It's, like, too neat to search the Usenet for articles that match a
-string, but it, like, totally @emph{sucks}, like, totally, to use one of
-those, like, Web browsers, and you, like, have to, rilly, like, look at
-the commercials, so, like, with Gnus you can do @emph{rad}, rilly,
-searches without having to use a browser.
-
-The @code{nnweb} backend allows an easy interface to the mighty search
-engine. You create an @code{nnweb} group, enter a search pattern, and
-then enter the group and read the articles like you would any normal
-group. The @kbd{G w} command in the group buffer (@pxref{Foreign
-Groups}) will do this in an easy-to-use fashion.
-
-@code{nnweb} groups don't really lend themselves to being solid
-groups---they have a very fleeting idea of article numbers. In fact,
-each time you enter an @code{nnweb} group (not even changing the search
-pattern), you are likely to get the articles ordered in a different
-manner. Not even using duplicate suppression (@pxref{Duplicate
-Suppression}) will help, since @code{nnweb} doesn't even know the
-@code{Message-ID} of the articles before reading them using some search
-engines (DejaNews, for instance). The only possible way to keep track
-of which articles you've read is by scoring on the @code{Date}
-header---mark all articles posted before the last date you read the
-group as read.
-
-If the search engine changes its output substantially, @code{nnweb}
-won't be able to parse it and will fail. One could hardly fault the Web
-providers if they were to do this---their @emph{raison d'être} is to
-make money off of advertisements, not to provide services to the
-community. Since @code{nnweb} washes the ads off all the articles, one
-might think that the providers might be somewhat miffed. We'll see.
-
-You must have the @code{url} and @code{w3} package installed to be able
-to use @code{nnweb}.
-
-Virtual server variables:
-
-@table @code
-@item nnweb-type
-@vindex nnweb-type
-What search engine type is being used. The currently supported types
-are @code{dejanews}, @code{dejanewsold}, @code{altavista} and
-@code{reference}.
-
-@item nnweb-search
-@vindex nnweb-search
-The search string to feed to the search engine.
-
-@item nnweb-max-hits
-@vindex nnweb-max-hits
-Advisory maximum number of hits per search to display. The default is
-100.
-
-@item nnweb-type-definition
-@vindex nnweb-type-definition
-Type-to-definition alist. This alist says what @code{nnweb} should do
-with the various search engine types. The following elements must be
-present:
-
-@table @code
-@item article
-Function to decode the article and provide something that Gnus
-understands.
-
-@item map
-Function to create an article number to message header and URL alist.
-
-@item search
-Function to send the search string to the search engine.
-
-@item address
-The address the aforementioned function should send the search string
-to.
-
-@item id
-Format string URL to fetch an article by @code{Message-ID}.
-@end table
-
-@end table
-
-
-@node Slashdot
-@subsection Slashdot
-@cindex Slashdot
-@cindex nnslashdot
-
-Slashdot (@file{http://slashdot.org/}) is a popular news site, with
-lively discussion following the news articles. @code{nnslashdot} will
-let you read this forum in a convenient manner.
-
-The easiest way to read this source is to put something like the
-following in your @file{.gnus.el} file:
-
-@lisp
-(setq gnus-secondary-select-methods
- '((nnslashdot "")))
-@end lisp
-
-This will make Gnus query the @code{nnslashdot} backend for new comments
-and groups. The @kbd{F} command will subscribe each new news article as
-a new Gnus group, and you can read the comments by entering these
-groups. (Note that the default subscription method is to subscribe new
-groups as zombies. Other methods are available (@pxref{Subscription
-Methods}).
-
-When following up to @code{nnslashdot} comments (or posting new
-comments), some light @sc{html}izations will be performed. In
-particular, text quoted with @samp{> } will be quoted with
-@code{blockquote} instead, and signatures will have @code{br} added to
-the end of each line. Other than that, you can just write @sc{html}
-directly into the message buffer. Note that Slashdot filters out some
-@sc{html} forms.