- From: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
- Date: Sat, 05 May 2007 14:43:41 +0100
- To: "John Foliot - WATS.ca" <foliot@wats.ca>
- CC: 'Lachlan Hunt' <lachlan.hunt@lachy.id.au>, www-html@w3.org, public-html@w3.org, tina@greytower.net, "'Patrick H.Lauke'" <redux@splintered.co.uk>, Philip-and-LeKhanh@Royal-Tunbridge-Wells.Org
John Foliot - WATS.ca wrote: > Lachlan Hunt wrote: >> No, it seems you missed the point of my questions. You and several >> others are arguing that we should drop <b> and <i> in favour of adding >> more specific semantic elements. I am asking you to be more specific. >> >>> (There, I just made the word "reason" purple in this HTML rich >>> exchange >> Purple? Sorry, plain text only. but I'll just pretend it was. > > ...and in a devilishly evil way, *that* is exactly the point. A > presentational artifact was lost on you - several in fact as the sentence > was marked with colors, bold and italicized text. And so some visual > meaning was lost to you - some of that visual rendering may have been for a > purpose, whilst other was pure whimsy. But you don't know, and can't know, > as you did not have the benefit of VISUAL PRESENTATION. Typical conversions from HTML to plain text often lose semantic information as well as presentational information, so this isn't a persuasive demonstration. I'd like to reframe it slightly. The problem with basic presentational markup is not /intrinsically/ one of media independence, but rather that it makes it difficult to infer authorial intentions. This is in itself a problem for people with learning disabilities or facing cultural and language barriers: and that means it's a big problem. In the UK population of 60 million, for example, perhaps 2 million have learning disabilities and 3 million do not speak English as their first language: http://www.learningdisabilities.org.uk/page.cfm?pagecode=ISBISTBI http://www.literacytrust.org.uk/Database/stats/EALstats.html Presentational information like colors, bold, and italic can all be represented in non-visual media. Talking browsers and screen readers may read italic and bold in a different voice and report changes in font. Braille actually has better provision for directly representing such typographic stylings than semantics: http://www.brl.org/formats/rule03.html But presentational markup becomes an accessibility problem in non-visual media for two reasons. The most important reason is efficiency. Visual media copes comparatively well with semantics being vaguely implied by typography because people can absorb layout and typography simultaneously with what is being formatted. This is difficult if your listening to an audio stream or reading a braille stream. Effective communication in a single channel depends on stripping out non-essential information. Otherwise too much time is spent extracting meaning from detritus. For example, many screen reader users turn most punctuation off. Properly written braille should only use its typographic stylings to convey semantic information, never purely for presentational effect. Print and braille have different conventions about what formatting to use for what semantics. For example, in a dictionary entry, the headword would typically receive special formatting in print, but not in braille. So braille displays rendering HTML glossaries would need <dfn> or <dt> to render correctly. <b> and <i> would result in a potentially confusing non-standard rendering. The second reason is quality of experience. Ship names and book titles may be italicized in print and braille, but they are not overly stressed in speech. If a talking browser knows a bit of text is a quotation or a thought, it can use a completely different voice just as you would do if you were reading material aloud. Given the high levels of illiteracy across the world and the greater naturalness of speech, it's not obvious that we should optimize the web for visual rather than aural presentation. In these ways even simple presentational markup /does/ indirectly interfere with media independence. But even for visual media, using <b> and <i> to imply semantics is risky when elements can also be styled by browsers and CSS. For example, let's say you use <i> for foreign phrases and you make a <blockquote> which contains a foreign phrase. If <blockquote> is styled italic by the author, the browser, or the user, then the foreign phrase's styling will be obliterated. Sadly, our current HTML/CSS stack has no easy solution to this problem, since CSS cannot select by style. i.e. you can't do something like: em {font-style:italic;} style("font-style:italic;") em {font-style:normal;} >> I wasn't asking if there are any use cases for <b> and <i>. I'm >> saying there are use cases for which bold and/or italic are >> typographical conventions, and I was asking you to pick at least one >> and answer the questions for it. > > And see, this is where it breaks down. The web is not about type-setting! > It's about conveying knowledge and ideas, without physical constraints - it > is that "power" that TBL keeps talking about - it transcends the printed > document and typographical conventions. You seem to be talking past what Lachlan was getting at. He's saying that typography is used to indicate (vaguely) semantics in print and in practice on the web, acknowledging that those semantics could (in theory) be expressed using semantic markup, and asking you to demonstrate the practical utility of such markup. He's basically implying that the usability benefits to users of more precise markup are too small to trump the usability costs to authors /in this case/, such that either the specification would be ignored or semantic markup misused. If true, this could actually interfere with the overall goal of transcending the printing document in other ways (e.g. non-linearity, easier navigability, instant connections, interactivity etc.). > In this scenario, it matters not whether it is <i> or <em> (as Raman said, > it is effectively the same to his screen reading tech at this point), but we > can now associate the reason why we've italicized (or emphasized) that > particular word or phrase. WYSIWYG editors could provide the means, when > "clicking the B button" to provide a "meaning" wizard/dialogue box - perhaps > pre-populated with some common reasons/meanings... Whether role or class is used, what should non-technical authors do when they cannot find a role or class to represent their meaning? Use <span>? I'm not suggesting this situation would be common, but it does bear thinking about. -- Benjamin Hawkes-Lewis
Received on Saturday, 5 May 2007 13:50:37 UTC