Applications Area Working Group                               S. Leonard
Internet-Draft                                             Penango, Inc.
Intended Status: Informational                         December 22, 2014
Expires: June 25, 2015



                      The text/markdown Media Type
                  draft-ietf-appsawg-text-markdown-05

Abstract

   This document registers the text/markdown media type for use with
   Markdown, a family of plain text formatting syntaxes that optionally
   can be converted to formal markup languages such as HTML.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors. All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document. Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.






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Table of Contents

   1. Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .  2
     1.1. This Is Markdown! Or: Markup and Its Discontents  . . . . .  2
     1.2. Markdown Is About Writing and Editing . . . . . . . . . . .  3
     1.3. Definitions . . . . . . . . . . . . . . . . . . . . . . . .  5
   2. Markdown Media Type Registration Application  . . . . . . . . .  5
   3. Fragment Identifiers  . . . . . . . . . . . . . . . . . . . . .  7
     3.1. Parameters  . . . . . . . . . . . . . . . . . . . . . . . .  8
   4.  Content Disposition and preview-type . . . . . . . . . . . . .  8
   5.  Example  . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 10
     6.1. Markdown Variants . . . . . . . . . . . . . . . . . . . . . 10
     6.2. Reserved Identifiers  . . . . . . . . . . . . . . . . . . . 11
     6.3. Standard of Review  . . . . . . . . . . . . . . . . . . . . 11
     6.4. Provisional Registration  . . . . . . . . . . . . . . . . . 11
   7. Security Considerations . . . . . . . . . . . . . . . . . . . . 12
   8. References  . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     8.1. Normative References  . . . . . . . . . . . . . . . . . . . 12
     8.2. Informative References  . . . . . . . . . . . . . . . . . . 13
   Appendix A.  Change Log  . . . . . . . . . . . . . . . . . . . . . 13
   Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 14


1. Introduction

1.1. This Is Markdown! Or: Markup and Its Discontents

   In computer systems, textual data is stored and processed using a
   continuum of techniques. On the one end is plain text: a linear
   sequence of characters in some character set (code), possibly
   interrupted by line breaks, page breaks, or other control characters.
   The repertoire of these control characters (a form of in-band
   signaling) is necessarily limited, and not particularly extensible.
   Because they are non-printing, these characters are also hard to
   enter with standard keyboards.

   Markup offers an alternative means to encode this signaling
   information by overloading certain characters with additional
   meanings. Therefore, markup languages allow for annotating a document
   in such a way that annotations are syntactically distinguishable from
   the printing information. Markup languages are (reasonably) well-
   specified and tend to follow (mostly) standardized syntax rules.
   Examples of formal markup languages include SGML, HTML, XML, and
   LaTeX. Standardized rules lead to interoperability between markup
   processors, but impose skill requirements on new users that lead to
   markup languages becoming less accessible to beginners. These rules
   also reify "validity": content that does not conform to the rules is



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   treated differently (i.e., is rejected) than content that conforms.

   In contrast to formal markup languages, lightweight markup languages
   use simple syntaxes; they are designed to be easy for humans to enter
   and understand with basic text editors. Markdown, the subject of this
   document, began as an /informal/ plain text formatting syntax
   [MDSYNTAX] and Perl script HTML/XHTML processor [MARKDOWN] targeted
   at non-technical users using unspecialized tools, such as plain text
   e-mail clients. [MDSYNTAX] explicitly rejects the notion of validity:
   there is no such thing as "invalid" Markdown. If the Markdown content
   does not result in the "right" output (defined as output that the
   author wants, not output that adheres to some dictated system of
   rules), the expectation is that the author should continue
   experimenting by changing the content or the processor to achieve the
   desired output.

   Since its development in 2004 [MARKDOWN], a number of web- and
   Internet-facing applications have incorporated Markdown into their
   text entry systems, frequently with custom extensions. Markdown has
   thus evolved into a kind of Internet meme [INETMEME] as different
   communities encounter it and adapt the syntax for their specific use
   cases. Markdown now represents a family of related plain text
   formatting syntaxes and implementations that, while broadly
   compatible with humans [HUMANE], are intended to produce different
   kinds of outputs that push the boundaries of mutual intelligibility
   between software systems.

   To support identifying and conveying Markdown, this document defines
   a media type and parameters that indicate the author's intent on how
   to interpret the Markdown. This registration draws particular
   inspiration from text/troff [RFC4263], which is a plain text
   formatting syntax for typesetting based on tools from the 1960s
   ("RUNOFF") and 1970s ("nroff", et. al.). In that sense, Markdown is a
   kind of troff for modern computing. A companion document [MDMTUSES]
   provides additional Markdown background and philosophy.

1.2. Markdown Is About Writing and Editing

     "HTML is a *publishing* format; Markdown is a *writing* format.
      Thus, Markdown's formatting syntax only addresses issues
      that can be conveyed in plain text." [MDSYNTAX]

   The paradigmatic use case for text/markdown is the Markdown editor:
   an application that presents Markdown content (which looks like an e-
   mail or other piece of plain text writing) alongside a published
   format, so that an author can see results instantaneously and can
   tweak his or her input in real-time. A significant number of Markdown
   editors have adopted "split-screen view" (or "live preview")



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   technology that looks like Figure 1:

+----------------------------------------------------------------------+
| File  Edit  (Cloud Stuff)  (Fork Me on GitHub)  Help                 |
+----------------------------------------------------------------------+
| [ such-and-such identifier ]                 [ useful statistics]    |
+----------------------------------++----------------------------------+
| (plain text, with                || (text/html, likely               |
|  syntax highlighting)            ||  rendered to screen)             |
|                                  ||                                  |
|# Introduction                    ||<h1>Introduction</h1>             |
|                                  ||                                  |
|## Markdown Is About Writing and  /|<h2>Markdown Is About Writing and |
/ Editing                          ||Editing</h2>                      |
|                                  ||                                  |
|> HTML is a *publishing* format;  ||<blockquote><p>HTML is a          |
|> Markdown is a *writing* format. || <em>publishing</em> format;      |
|> Thus, Markdown's formatting     || Markdown is a <em>writing</em>   |
|> syntax only addresses issues    || format. Thus, Markdown's         |
|> that can be conveyed in plain   <> formatting syntax only addresses |
|> text. [MDSYNTAX][]              || issues that can be conveyed in   |
|                                  || plain text. <a href="http://darin/
|The paradigmatic use case for     |/gfireball.net/projects/markdown/sy/
|`text/markdown` is the Markdown   |/ntax#html" title="Markdown: Syntax/
|editor: an application that       |/: HTML">MDSYNTAX</a>              |
|presents Markdown content         ||</p></blockquote>                 |
|...                               ||                                  |
|                                  ||<p>The paradigmatic use case for  |
|[MDSYNTAX]: http://daringfireball./| <code>text/markdown</code> is the|
/net/projects/markdown/syntax#html || Markdown editor: an application  |
|"Markdown: Syntax: HTML"          || that presents Markdown content   |
|                                  || ...</p>                          |
+----------------------------------++----------------------------------+

 LEGEND: "/" embedded in a vertical line represents a line-continuation
  marker, since a line break is not supposed to occur in that content.

          Figure 1: Markdown Split-Screen/Live Preview Editor

Users on diverse platforms SHOULD be able to collaborate with their
tools of choice, whether those tools are desktop-based (MarkdownPad,
MultiMarkdown Composer), browser-based (Dillinger, Markable), integrated
widgets (Discourse, GitHub), general-purpose editors (emacs, vi), or
plain old "Notepad". Additionally, users SHOULD be able to identify
particular areas of Markdown content when the Markdown becomes
appreciably large (e.g., book chapters and Internet-Drafts--not just
blog posts). Users SHOULD be able to use text/markdown to convey their
works in progress, not just their finished products (for which full-



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blown markups ranging from text/html to application/pdf are
appropriate). This registration facilitates interoperability between
these Markdown editors by conveying the syntax of the particular
Markdown variant and the desired output format.

1.3. Definitions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   Since Markdown signifies a family of related formats with varying
   degrees of formal documentation and implementation, this
   specification uses the term "variant" to identify such formats.

2. Markdown Media Type Registration Application

   This section provides the media type registration application for the
   text/markdown media type (see [RFC6838], Section 5.6).

    Type name: text

    Subtype name: markdown

    Required parameters:

     charset: Per Section 4.2.1 of [RFC6838], charset is REQUIRED. There
       is no default value. [MDSYNTAX] clearly describes Markdown as a
       writing format; its syntax rules operate on characters
       (specifically, on punctuation) rather than code points. Neither
       [MDSYNTAX] nor many popular implementations at the time of this
       registration actually require or assume any particular character
       set. Many Markdown processors will get along just fine by
       operating on character codes that lie in printable US-ASCII,
       blissfully oblivious to coded values outside of that range.

    Optional parameters:

     variant: An optional identifier that serves as a "hint" to the
       recipient of the specific Markdown variant that the author
       intended. When omitted, there is no hint; the interpretation is
       entirely up to the receiver and context. This identifier is plain
       US-ASCII and case-insensitive. To promote interoperability,
       identifiers MAY be registered in the registry defined in Section
       6. If a receiver does not recognize the variant identifier, the
       receiver MAY present the identifier to a user to inform him or
       her of it.




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     Other parameters MAY be included with the media type. The variant
     SHOULD define the semantics of such parameters. Additionally, the
     variant MAY be registered under another media type; this
     text/markdown registration does not preclude other registrations.

    Encoding considerations: Text.

    Security considerations:

     Markdown interpreted as plain text is relatively harmless. A text
     editor need only display the text. The editor SHOULD take care to
     handle control characters appropriately, and to limit the effect of
     the Markdown to the text editing area itself; malicious Unicode-
     based Markdown could, for example, surreptitiously change the
     directionality of the text. An editor for normal text would already
     take these control characters into consideration, however.

     Markdown interpreted as a precursor to other formats, such as HTML,
     carries all of the security considerations as the target formats.
     For example, HTML can contain instructions to execute scripts,
     redirect the user to other webpages, download remote content, and
     upload personally identifiable information. Markdown also can
     contain islands of formal markup, such as HTML. These islands of
     formal markup may be passed as-is, transformed, or ignored (perhaps
     because the islands are conditional or incompatible) when the
     Markdown is processed. Since Markdown may have different
     interpretations depending on the tool and the environment, a better
     approach is to analyze (and sanitize or block) the output markup,
     rather than attempting to analyze the Markdown.

   Interoperability considerations:

     Markdown variations (some might say "innovations") are designed to
     be broadly compatible with humans ("humane"), but not necessarily
     with each other. Therefore, syntax in one Markdown derivative may
     be ignored or treated differently in another derivative. The
     overall effect is a general degradation of the output, proportional
     to the quantity of variant-specific Markdown used in the text. When
     it is desirable to reflect the author's intent in the output, stick
     with the variant identified in the variant parameter.

   Published specification: This specification; [MDSYNTAX].

   Applications that use this media type:

     Markdown conversion tools, Markdown WYSIWYG editors, and plain text
     editors and viewers; markup processor targets indirectly use
     Markdown (e.g., web browsers for Markdown converted to HTML).



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   Fragment identifier considerations:

     See Section 4.

   Additional information:

     Magic number(s): None
     File extension(s): .md, .markdown
     Macintosh file type code(s):
       TEXT. A uniform type identifier (UTI) of
       "net.daringfireball.markdown", which conforms to "public.plain-
       text", is RECOMMENDED [MDUTI]. See [MDMTUSES] for other
       considerations.

   Person & email address to contact for further information:

     Sean Leonard <dev+ietf@seantek.com>

   Restrictions on usage: None.

   Author/Change controller: Sean Leonard <dev+ietf@seantek.com>

   Intended usage: COMMON

   Provisional registration? No

   Implementations SHOULD record the value of the variant parameter (and
   other parameters if defined by the variant) along with the Markdown
   content when the content leaves the domain of Internet media type-
   capable formats. Strategies for doing so are discussed in [MDMTUSES].

   The Content-Disposition header (particulalry the preview-type
   parameter) can be used with Markdown content. See Section 4.


3. Fragment Identifiers

   [MARKDOWN] does not define any fragment identifiers, but some
   variants do, and many types of Markdown processor output (e.g., HTML
   or PDF) will have well-defined fragment identifiers. Which fragment
   identifiers are available for a given document are variant-defined.

   When encoded in a URI, characters that are outside of the fragment
   production of [RFC3986] are percent-encoded. The default encoding
   (character set) of percent-encoded octets in URIs is the same as the
   Markdown content, which is identified by the charset parameter or by
   other contextual means. Fragment identifiers SHOULD be considered
   case-sensitive, which maintains consistency with HTML. Variants MAY



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   override the guidance in this paragraph. [[NB: citation necessary to
   HTML4/HTML5?]]

   At least the first equals sign "=" SHOULD be percent-encoded to
   prevent ambiguity as described in the following section.

3.1. Parameters

   Similar to application/pdf [RFC3778] and text/plain [RFC5147], this
   registration permits a parameter syntax for fragment identifiers. The
   syntax is a parameter name, the equals sign "=" (which MUST NOT be
   percent-encoded), and a parameter value. To the extent that multiple
   parameters can appear in a fragment production, the parameters SHALL
   be separated by the ampersand "&" (which MUST NOT be percent-
   encoded).

   The only parameter defined in this registration is "line", which has
   the same meaning as [RFC5147] (i.e., counting is zero-based). For
   example: "#line=10" identifies the eleventh line of Markdown input.
   Implementers should take heed that different environments and
   character sets may have a wide range of code sequences to divide
   lines.

   Markdown variants are free to define additional parameters.

   [[NB: This draft does not import all of text/plain's fragment
   identifier schemes, mainly because the utility of the other schemes
   is far from obvious. Implementing line= is not difficult but char= is
   more difficult since "character" has various meanings that will skew
   the numbering significantly as the content grows in length; the other
   integrity check things simply do not seem to be particularly
   useful.]]

4.  Content Disposition and preview-type

   The Content-Disposition header [RFC2183] conveys presentational
   information about a MIME entity, using a type and set of parameters.
   The parameter "preview-type" is defined here for Markdown content.

   When present, "preview-type" indicates the Internet media type (and
   parameters) of the preview output desired from the processor by the
   author. With reference to the "paradigmatic use case" (i.e.,
   collaborative Markdown editing) in Section 1.3, the output-type
   parameter primarily affects the "right-hand" side of a Markdown
   editor. There is no default value: when absent, a Markdown user agent
   can render or display whatever it wants.

   The value of this parameter is an Internet media type with optional



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   parameters. The syntax (including case sensitivity considerations) is
   the same as specified in [RFC2045] for the Content-Type header (with
   updates over time, e.g., [RFC2231] and [RFC6532]).

   Implementations SHOULD anticipate and support HTML (text/html) and
   XHTML (application/xhtml+xml) output, to the extent that a syntax
   targets those markup languages. These types ought to be suitable for
   the majority of current purposes. However, Markdown is increasingly
   becoming integral to workflows where HTML is not the target output;
   examples range from TeX, to PDF, to OPML, and even to entire e-books
   (e.g., [PANDOC]).

   The reflexive media type "text/markdown" in this parameter value
   means that the author does not want to invoke Markdown processing at
   all: the receiver SHOULD present the Markdown source as-is.

   The preview-type parameter can be used for other types of content,
   but the precise semantics are not defined here.

5.  Example

   The following is an example of Markdown as an e-mail attachment:

    MIME-Version: 1.0
    Content-Type: text/markdown; charset=UTF-8; variant=Original
    Content-Disposition: attachment; filename=readme.md;
     preview-type="application/xhtml+xml"

    Sample HTML 4 Markdown
    =============

    This is some sample Markdown. [Hooray!][foo]
    (Remember that link identifiers are not case-sensitive.)

    Bulleted Lists
    -------

    Here are some bulleted lists...

    * One Potato
    * Two Potato
    * Three Potato

    - One Tomato
    - Two Tomato
    - Three Tomato

    More Information



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    -----------

    [.markdown, .md](http://daringfireball.net/projects/markdown/)
    has more information.

    [fOo]: http://example.com/loc 'Will Not Work with Markdown.pl-1.0.1'

6.  IANA Considerations

   IANA is asked to register the media type text/markdown in the
   Standards tree using the application provided in Section 2 of this
   document.

   IANA is asked to register "preview-type" in the Content Disposition
   Parameters subregistry of the Content Disposition Values and
   Parameters registry.

6.1. Markdown Variants

   IANA is also asked to establish a registry called "Markdown
   Variants". While the registry is being created in the context of the
   text/markdown media type, the registry is intended for broad
   community use, so protocols and systems that do not rely on Internet
   media types can still tag Markdown content with a common variant
   identifier. Each entry in this registry shall consist of basic
   information about the variant:

      Identifier
      Name
      Description
      Additional Parameters (optional)
      Fragment Identifiers (optional)
      References
      Contact Information
      Expiration Date (if provisional)

   While the variant parameter is "plain US-ASCII" (see registration
   template), the Identifier field (and by implication, all registered
   identifiers) SHALL conform to the ABNF:

     ALPHA [*(%d33-126) (ALPHA / DIGIT)]

   For style and compatibility reasons, the Identifier field SHOULD
   conform to the ABNF:

     ALPHA 1*( ["-" / "." / "_" / "~"] 1*(ALPHA / DIGIT) )

   I.e., the identifier MUST start with a letter and MAY contain



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   punctuation in the middle, but not at the end: the last character
   MUST be alphanumeric. The second production uses the same characters
   as the "unreserved" rule of [RFC3986], and is designed to be
   compatible with characters in other identification systems, e.g.,
   filenames. Since the identifier MAY be displayed to a user--
   particularly in cases where the receiver does not recognize the
   identifier--the identifier SHOULD be rationally related to the
   vernacular name of the variant.

   The Name, Description, Additional Parameters, Fragment Identifiers,
   References, and Contact Information fields SHALL be in a Unicode
   character set (e.g., UTF-8).

6.2. Reserved Identifiers

   The registry SHALL have the following identifiers RESERVED. No one is
   allowed to register them (or any case variations of them).
      Standard
      Common
      Markdown

6.3. Standard of Review

   Registrations are made on a First-Come, First-Served [RFC5226] basis
   by anyone with a need to interoperate. While documentation is
   required, any level of documentation is sufficient; thus, neither
   Specification Required nor Expert Review are warranted. The checks
   prescribed by this section can be performed automatically.

   All references (including contact information) MUST be verified as
   functional at the time of the registration.

   If a registration is being updated, the contact information MUST
   either match the prior registration and be verified, or the prior
   registrant MUST confirm that the updating registrant has authority to
   update the registration. As a special "escape valve", registrations
   can be updated with IETF Review [RFC5226]. [[NB: Two purposes: 1) to
   deal with "harmful" registrations (stale references are not a
   sufficient justification); 2) to deal with registrations that are
   IETF registrations, like RFC-related Markdown (but this could be
   handled by listing the IETF as the contact organization, right?).]]
   All fields may be updated except the variant identifier, which is
   permanent: not even case may be changed.

6.4. Provisional Registration

   Any registrant may make a provisional registration to reserve a
   variant identifier. Only the variant identifier and contact



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   information fields are required; the rest are optional. Provisional
   registrations expire after three months, after which time the variant
   identifier may be reused. To make a registration permanent, a
   registrant simply needs to complete a permanent registration with the
   same identifier as the provisional registration.

7. Security Considerations

   See the Security considerations entry in Section 2.

8. References

8.1. Normative References

   [MARKDOWN] Gruber, J., "Daring Fireball: Markdown", December 2004,
              <http://daringfireball.net/projects/markdown/>.

   [MDSYNTAX] Gruber, J., "Daring Fireball: Markdown Syntax
              Documentation", December 2004,
              <http://daringfireball.net/projects/markdown/syntax>.

   [MDUTI]    Gruber, J., "Daring Fireball: Uniform Type Identifier for
              Markdown", August 2011,
              <http://daringfireball.net/linked/2011/08/05/markdown-
              uti>.

   [RFC2045]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part One: Format of Internet Message
              Bodies", RFC 2045, November 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2231]  Freed, N. and K. Moore, "MIME Parameter Value and Encoded
              Word Extensions: Character Sets, Languages, and
              Continuations", RFC 2231, November 1997.

   [RFC2854]  Connolly, D. and L. Masinter, "The 'text/html' Media
              Type", RFC 2854, June 2000.

   [RFC3778]  Taft, E., Pravetz, J., Zilles, S., and L. Masinter, "The
              application/pdf Media Type", RFC 3778, May 2004.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66, RFC
              3986, January 2005.

   [RFC5147]  Wilde, E. and M. Duerst, "URI Fragment Identifiers for the



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              text/plain Media Type", RFC 5147, April 2008.

   [RFC5226]  Narten, T., and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", RFC 5226, May 2008.

   [RFC5322]  Resnick, P., Ed., "Internet Message Format", RFC 5322,
              October 2008.

   [RFC6532]  Yang, A., Steele, S., and N. Freed, "Internationalized
              Email Headers", RFC 6532, February 2012.

   [RFC6838]  Freed, N., Klensin, J., and T. Hansen, "Media Type
              Specifications and Registration Procedures", BCP 13, RFC
              6838, January 2013.

8.2. Informative References

   [HUMANE]   Atwood, J., "Is HTML a Humane Markup Language?", May 2008,
              <http://blog.codinghorror.com/is-html-a-humane-markup-
              language/>.

   [INETMEME] Solon, O., "Richard Dawkins on the internet's hijacking of
              the word 'meme'", June 2013,
              <http://www.wired.co.uk/news/archive/2013-06/20/richard-
              dawkins-memes>, <http://www.webcitation.org/6HzDGE9Go>.

   [MDMTUSES] Leonard, S., "text/markdown Use Cases", draft-seantek-
              text-markdown-use-cases-00 (work in progress), October
              2014.

   [PANDOC]   MacFarlane, J., "Pandoc", 2014,
              <http://johnmacfarlane.net/pandoc/>.

   [RFC4263]  Lilly, B., "Media Subtype Registration for Media Type
              text/troff", RFC 4263, January 2006.


Appendix A.  Change Log

   This draft is a continuation from draft-ietf-appsawg-text-markdown-
   04.txt. These technical changes were made:

      1.  Added preview-type Content Disposition parameter.
      2.  Updated example.
      3.  Fleshed out more of the registration procedures.
      4.  Simplified the text of the fragment identifiers.
      5.  Removed vestiges of the old syntax and output-type parameters.
      6.  Discussed the meaning of "variant" in the context of Markdown.



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Author's Address

   Sean Leonard
   Penango, Inc.
   5900 Wilshire Boulevard
   21st Floor
   Los Angeles, CA  90036
   USA

   EMail: dev+ietf@seantek.com
   URI:   http://www.penango.com/








































Leonard                    Exp. June 25, 2015                  [Page 14]