Created 21 September 2003
There seem to be widely-held misconceptions about software standards. People treat them as if they were laws, or moral commandments, or guarantees of success. They’re not. They’re just shorthands.
As an example, Jeffrey Zeldman has written a well-regarded book called Designing With Web Standards. It is about using XHTML to structure content, and CSS to apply style. He argues cogently that this is a good way to build web pages, and in fact, it is designing with web standards.
But the “wrong” way of creating web pages (using HTML where cosmetics is mixed in with content, and big tables control the layout of pages) is also perfectly compliant with web standards. The dreaded <font> tag works because an HTML standard says what it should do, and the browser manufacturers implemented the standard. Using tables to create page layouts works for the same reason. Everyone used the standard. We still ended up with the mess Zeldman describes.
Now Zeldman may be right that his is the better way to create pages, but both ways are based on standards issued by the W3C, so there must be more to it than simply “designing with web standards”. A better title for the book would have been “Designing with XHTML and CSS”, or “Designing Modern Web Sites”, or “Separating Content from Cosmetics”.
I’m not criticizing the message of Zeldman’s book: it’s a good one. It’s just misleading to claim that the “right” way is right because it’s based on standards. The “wrong” way is also based on standards, which is perfect proof that designing with standards doesn’t guarantee you a well-designed system architecture.
There’s an old joke:
The great thing about standards is there are so many to choose from.
The humor in this joke derives from the mistaken idea that once a standard is written, everyone should use it, or the mistaken idea that a standard defines the best way to do something. If a standard is so great, why do we need more than one for the same purpose?
When an organization creates a standard, it doesn’t mean that everyone must conform to the standard. All it really means is that hundreds of pages of details can be summarized with a simple phrase. The CSS 2.0 standard doesn’t anywhere say that people must use it. What it says is that a hugely complex set of characteristics, functions and features can be described by saying “CSS 2.0”, and that everyone agrees what that means.
This is a good thing. I can read the standard, and write a page that will work properly if the semantics in the standard are delivered as promised. Then I can read about a browser, and see that it says it supports CSS 2.0. Unless someone is lying, or there are bugs, then I know that my page will work in that browser. I’ve used the shorthand of “CSS 2.0” to avoid having to read a 200-page manual about how the browser works, or test each little feature to see what the browser does with it.
CSS is a good standard, by which I mean that it is well designed, and does its job well. Even better, its place in the world has been well thought out by its authors, and a system built upon it will have the power of a good architecture behind it. But that’s not because it is a standard. It’s because it’s a good standard.
Usually, when an organization sets out to write a new standard, they’ll try to incorporate the latest best thinking, so often recent standards will be better architecturally than older ones. But there’s no guarantee of that, and there’s no guarantee that the most recent standard is the best one for your purposes. You have to understand what it really offers you other than buzzword compliance.
Not all standards are created equal. Some, such as HTML 3.2, are written to codify existing practice. Others, such as XSLT, are written to introduce new technology. The former tend to have a broader adoption, while the latter tend to be more thoughtfully designed. Understanding which type of standard you are considering may help you to use it appropriately.
To top it off, there are plenty of bad standards. HTML 3.2 may be one of them, because of its careless mixing of content and style, among other reasons. The XML standard includes the definition of DTDs for describing classes of XML documents. Once it was finished, work began almost immediately on XML Schema, which could obsolete DTDs.
So use standards for what they are good for: giant dictionary definitions of pieces of system architecture. Don’t assume that they are good design, or appropriate for your work. Standards can save us time by defining syntax and semantics, but they can’t be used to skip our own thinking about architecture.
And when you use standards, keep in mind what about them makes the useful. Just being “standard” isn’t enough. If you lose sight of why your system is built the way it is, you’ll make bad decisions about its future. XHTML and CSS are good things, but not simply because they are standards. Being standardized is one of the good things about them, but more important is what they can actually do.
- My blog, where other similar topics are discussed.