+@menu
+* Client Certificates for Gemini:: Accessing secure gemini pages
+* Hiding preformatted text in text/gemini documents:: An accessibility option
+@end menu
+
+@node Client Certificates for Gemini, Hiding preformatted text in text/gemini documents, Gemini support, Gemini support
+@section Client Certificates for Gemini
+
+Gemini makes explicit use of the client certificate mechanism that TLS
+provides for allowing clients to authenticate themselves with servers.
+The Gemini specification suggests two distinct classes of client
+certificates: short-lived certificates used to identify you for a single
+session, and more permanent certificates used to identify you over a
+longer time period.
+
+When Elpher receives a request for a client certificate from a server,
+it will present you with the option to create and use a single-use
+``throwaway'' certificate, or to use a ``persistent''
+certificate (optionally creating it or installing pre-existing key and
+certificate files).
+
+Certificate creation in Elpher requires an installation of OpenSSL, and
+---in particular---that Elpher be able to run the @command{openssl} command-line
+utility. By default, Elpher assumes that the @command{openssl} is on the
+system path, but the precise location can be set by customizing the
+@code{elpher-openssl-command} variable.
+
+Each generated certificate results in the creation of a .key file and
+a .crt file. In the case of a throwaway certificate, these files are
+stored in the temporary directory indicated by the Emacs variable
+@code{temporary-file-directory} and are deleted when ``forgotten''
+(as described below).
+
+In the case of persistent certificates, these files are stored in the
+folder defined by the Elpher variable
+@code{elpher-certificate-directory}, and are never deleted by Elpher.
+(Of course you can delete them yourself whenever you like.)
+The base name of the files (i.e. sans extension) is what Elpher uses
+to identify the certificate.
+
+Using throwaway certificates is as simple as pressing the @key{t}
+key at the prompt which appears following a certificate request from
+a server. There is nothing more to do.
+
+Using a persistent certificate requires instead selecting @key{p} from the same
+menu. This will result in Elpher asking you for the name identifying
+the certificate. This entry autocompletes to the list of known certificate
+names, so you can use @key{TAB} to display the list.
+
+In the case that you choose a name that does not belong to the list of
+known certificates, Elpher will offer to create one for you or to
+``install'' one from existing key and certificate files.
+Pressing the @key{n} key will cause Elpher to begin the process of
+creating a new persistent certificate, using some additional
+details for which you will be prompted.
+Alternatively, pressing the @key{i} key will cause Elpher to ask for the
+locations of existing key and certificate files to add to
+@code{elpher-certificate-directory} under the chosen name.
+
+Once a certificate is selected, it will be used for all subsequent
+gemini requests involving URLs begining with the URL for for which the
+certificate was created. It is immediately ``forgotten'' when a TLS
+connection to a non-matching URL is attempted, or the following command
+is issued:
+
+@table @asis
+@keycmd{@key{F},elpher-forget-certificate}
+Causes Elpher to immediately forget any currently-loaded client certificate.
+@end table
+
+In either case, ``forgetting'' means that the details of the key and
+certificate file pair are erased from memory. Furthermore, in the case
+of throw-away certificates, the corresponding files are deleted.
+
+Persistant client certificates can be added to the alist contained in the
+customization variable @code{elpher-certificate-map} so that they are
+automatically activated whenever a gemini page with the matching URL
+prefix is visited.
+
+@node Hiding preformatted text in text/gemini documents, , Client Certificates for Gemini, Gemini support
+@section Hiding preformatted text in text/gemini documents
+
+Preformatted text is often used to display ``ASCII art'' or other
+similar text-based artwork. While for many this is a fun way to
+introduce personality into their gemini documents, such text can
+pose difficulties for screen readers.
+
+Setting the @code{elpher-gemini-hide-preformatted} customization option
+to non-nil causes Elpher to hide all preformatted text blocks by
+default. In place of the preformatted text, Elpher instead displays the
+``alt text'' (if any is available), along with a button which can be
+used to make specific blocks visible as required.
+
+Other related customization options are
+@code{elpher-gemini-preformatted-toggle-label}, which is the label used
+for the toggle button, and
+@code{elpher-gemini-preformatted-toggle-bullet}, which is the margin
+string used to distinguish the line replacing the preformatted text.
+
+@node Finger support, Local files, Gemini support, Top
+@chapter Finger support
+
+Incidentally, Elpher has native support for querying finger servers.
+Of course, one could argue that this functionality is more easily
+provided by one's local telnet client. However finger URLs do appear
+on occasion in gopherspace, and it's nice to be able to open them
+in place.
+
+Elpher interprets @code{finger://} URLs as follows:
+
+@itemize
+
+@item
+The host is determined by the host name portion of the URL.
+
+@item
+In the case that the @emph{file name} portion of the URL is non-empty (besides
+the leading slash), this is interpreted as the user to finger.
+
+@item
+Otherwise, the @emph{user} portion of the URL is interpreted as the user to finger.
+
+@item
+If no user is provided, the root directory of the finger server is requested.
+
+@end itemize
+
+Thus @code{finger://user@@hostname} and @code{finger://hostname/user} are both equivalent.
+
+(The precedence of the /user notation over the user@ notation reflects a
+preference of the community.)
+
+@node Local files, About pages, Finger support, Top
+@chapter Local files
+
+Elpher supports opening local files via @samp{file:} URLs.
+
+For instance, pressing @key{g} and entering @code{file:~/document.gmi}
+will load the file named @samp{document.gmi} in your home directory,
+provided this file exists.
+
+Files opened in this way are rendered according to their name, and in
+particular their extension. The current mappings are as follows:
+
+@table @asis
+
+@item @samp{txt}
+
+Plain text documents. All local text files are assumed to be
+UTF-8-encoded.
+
+@item @samp{gophermap},@samp{gopher}
+
+Gophermap files, i.e. files containing a valid directory list as specified
+by RFC 1436.
+
+@item @samp{gemini},@samp{gmi}
+
+Gemini documents (i.e. documents of MIME type ``text/gemini''). All
+local gemini files are assumed to be UTF-8-encoded.
+
+@item @samp{html},@samp{htm}
+
+HTML documents. All local HTML files are assumed to be UTF-8-encoded.
+
+@item @samp{png},@samp{jpg},@samp{jpeg},@samp{gif},@samp{bmp},@samp{tif},@samp{tiff}
+
+Image files.
+
+@item Anything else
+A binary document, which elpher will simply offer to save somewhere
+else. (Obviously this is not useful in its own right, but there's not
+much that elpher can sensibly do with unknown binary files.)
+
+@end table
+
+
+@node About pages, ANSI support, Local files, Top
+@chapter About pages
+
+Like other browsers, elpher makes certain internally-generated pages
+such as the initial welcome page, the bookmarks page, the history
+stack and the list of visited pages pages accessible as URLs with
+the ``about:'' type.
+
+This means that these pages can be bookmarked and, more usefully,
+added to a local file to be rendered as a user-defined start page.
+
+To see the address of a special page, simply visit the page and
+press @key{I}.
+
+@node ANSI support, Customization, About pages, Top
+@chapter ANSI support
+
+Depending on which parts of the gopher/gemini universe you frequent,
+you may occasionally stumble on sites which use ANSI escape codes to
+either produce specific characters or to colour text.
+
+By default, elpher uses Emacs' built-in ANSI rendering library,
+@samp{ansi-color}, to process ANSI codes. This robustly interprets
+the escape codes but only supports 8 colours. Any colours unsupported
+by the library are simply stripped, leaving uncoloured text in the
+majority of cases.
+
+To drastically improve the number of colours produced, install the
+@samp{xterm-color} package from MELPA. This package will be automatically
+used by elpher if it is available, and supports 256 colours.
+This should be sufficient to properly render many ANSI colour
+gopher holes and gemini capsules quite nicely.
+
+In case you prefer to completely strip out the ANSI escape codes entirely
+by customizing the @code{elpher-filter-ansi-from-text} variable.
+
+
+@node Customization, Command Index, ANSI support, Top