If you're a conscientious web developer you make sure when you update static assets, like CSS and javascript, that your site forces a visitor to download a fresh copy with the updated code in it. This is otherwise known as cache-busting.
A furore has erupted over the past couple of days within a section of the web development community over a decision by Microsoft to require web developers to add a meta tag to their pages to define what version of Internet Explorer a site has been designed for. I'm not going to go into the pros and cons of this decision as it's been comprehensively covered elsewhere.
I recently had a discussion with a client that I'd already produced a template for who said they wanted to change the primary navigation items at the top of each page. As the site hadn't gone live yet (they were producing it themselves – I'd simply done the graphic and template design for them), I didn't see much problem with fulfilling their request. But it was a two-part request and the part that raised a warning flag for me was that they wanted the navigation to be flexible enough for them to be able to make further changes easily at some point in the future.
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