If you use a web-based email client, you've probably received an email before that you didn't notice because there's not any kind of notification. If you're a Gmail user, that problem is solved. Gmail just launched desktop notifications for anyone using Chrome as their web browser. After you turn the notifications on, you'll see a little box pop up anytime you receive an email or chat message.
If you want to try this feature out, make sure you're using Google Chrome, and go into the settings section of your gmail account. About half-way down on the main settings page, you'll see a "Desktop Notifications" option which you should enable. That's all there is to it.
Warning: The rest of this post is going to be much more technical and pointless. If you're not into reading rants aimed at programmers, you might want to stop reading.
One thing that stands out about the new Gmail notifications is that they're the first instance of HTML5 notifications I've ever seen in a real webapp. HTML5 is one of the hottest buzz words in tech right now - every company is talking about how they plan to use it in the future - but there really aren't very many examples of HTML5 actually being used by any major software products. Additionally, HTML5 is supposed to be an open web standard, but Gmail notifications only work in Chrome for some reason. This all begs the question: What is HTML5 and why do tech bloggers and software companies spend so much time talking about it?
But before talking about what HTML is, let's go over what it isn't? HTML5 is not CSS3. That means that when you see web sites using fancy fonts, rounded corners, shadows, and CSS transitions, that's not HTML5. It's all very cool and modern, but it's just not HTML5.
There are really only a few features users will notice that are entirely within the domain of HTML5. The ones that seem important to me are: The canvas element (although that's been around for a while and it works in IE I think, so I'm not entirely clear on how that counts), offline storage, drag-n-drop file uploads, and desktop notifications. There are some other more obscure features, but I think I named the big ones.
Of that list of features, I've only ever seen the file uploads in Gmail and LucidChart. The canvas element is used more commonly, but like I mentioned, that doesn't really count as HTML5 in my book. I don't know of a single web service that uses HTML5 offline storage, and Google has just now added the first instance of desktop notifications I've ever seen. So why is it that HTML5 is the second most overused tech buzz word (after "cloud") despite the fact that it appears to be vapor-ware? If everyone's talking about HTML5, why isn't anyone using it?
Furthermore, the Gmail notifications only work in Chrome. What's the point of using a web standard if it only works in one browser? Doesn't that sort of defeat the whole point of having standards?
There's one simple conclusion to draw from this incoherent rant: HTML5 is not a web standard. It will be a web standard one day, but it's not right now. Firefox, Chrome, Safari and Opera all have completely different support for HTML5 which means you need to write up to four different versions of your code to support HTML5 functionality... and it still won't work in the world's most popular browser (IE).