When you think of standards, you're likely to think of the standards of which we now are supposed to use to design web sites. But that's not the only place where standards are being used. Computers themselves and the way they boot, that's a standard. I'll talk a bit about email standards, then jump into the web standards that seem to be first-in-line.
When you send or recieve an e-mail, your client is conforming to certain standards so that the servers know who sent it, and where it's going, along with all the other information behind the scenes. Why is that important? Well, if there weren't a standard to follow, things will get nice and screwed up all the time. Some emails wouldn't get sent, some not recieved. So all of the servers and clients need to follow the standards so that it can take place. Of course, with different protocols for email, they each have their own settings, but nonetheless, it requires standards to keep the Internet somewhat stable.
But yes, let's take a look at the standards that web designs should be using to build their sites. When you look at this site, it should validate as XHTML 1.0 Transitional. I coded it to do that. Why? Well, any modern browser is generally coded to render pages coded in the standards properly. If you look at this in a browser that doesn't support CSS, chances are you're going to leave it, as it's quite ugly looking (and hard to follow.)
Here's my theory about standards. When we can do whatever it is we want, and add new this or new that, we tend to create some facsinating ideas. Most of which end up duplicating and having multiple ways of doing it. With all these ways, it becomes hard for the client developers to keep up with them and implement them so that it can support as many methods as possible. This also makes the coding language sloppy, without structure as to how things should go. Once you start overlooking how things are done, you can choose the best ways and parse out the rest, leaving just one or two methods to accomplish something. Then you start looking at the language structure, and being conforming rules of where things should be placed, where they can be placed and how it will all work together. Once you get that all done, there's a guideline of which the coders can follow.
What puzzled me before was, "We have standards, why aren't they being used by everyone?" The answer came to me. It takes time, and implementation. Standards for web design have been around for a very long time, but it's only been the last 2 years that people have started to take them seriously. Many large sites are coded in a way that makes it so difficult to make the compliant, that they would have to recode the entire thing, salvaging pieces where they can. Another reason is the age group of coders. The coders that have been around for a very long time often don't like the switch to the new language, and find it difficult to trade off their old habits for the new ones. It's much easier to code HTML without worrying about whether it will validate or not. And even easier then if you don't care if it doesn't render outside the browser you use.
Practice will show that if you conform to the standards wherever possible, you'll be a lot better off. This doesn't mean you should break off and try something new. We need to ideas for web design. ActiveX is dying and and Flash isn't progressing much right now.
But remember, the less the visitor has to do in order to view your site, the more likely they'll enjoy the visit.