This article was originally published under Search Engine Land.

Wouldnโ€™t it be great if all those whiz-bang Web 2.0 interactive elements based on AJAX (Asynchronous JavaScript and XML) and Flashโ€”such as widgets and gadgets and Google Maps mashupsโ€” were search engine optimal?

Unfortunately, thatโ€™s not the case. In fact, these technologies are inherently unfriendly to search engine spiders. So, if you intend to harness Web 2.0 technologies for wider syndication, increased conversion, improved usability and greater customer engagement, youโ€™d better read on or youโ€™ll end up missing the boat when it comes to better search engine rankings.

When it comes to AJAX and Flash, the onus is on you to render them search engine friendly. The major search engines just canโ€™t cope with these Web 2.0 technologies very well at all.

Flash not friendly

Letโ€™s start with Flash, a technology with which many of us already are familiar. Some search engines, including Google, have rudimentary means of extracting content and links from Flash. Nonetheless, any content or navigation embedded within Flash will, at best, rank poorly in comparison to a static, HTML-based counterpart, and at worst, not even make it into the search engineโ€™s index.

Googleโ€™s view on Flash is that it doesnโ€™t provide a user-friendly experience. Flash is wholly inaccessible to the vision-impaired, unrenderable on devices such as mobile phones and PDAs, and canโ€™t be accessed without broadband connectivity.

In particular, Google frowns on navigational elements presented exclusively in Flash. Given this stance, Google isnโ€™t likely to make big improvements on how it crawls, indexes and ranks Flash files anytime soon. So, itโ€™s in your hands to either replace those Flash elements with a more accessible alternative like CSS/DHTML or to employ a Web design approach known as โ€œprogressive enhancement,โ€ whereby designs are layered in a concatenated manner to provide an alternative experience for non-Flash users. This way, all users, including search engine spiders, will be able to access your content and functionality.

An example of progressive enhancement in action can be found at Amazon.comโ€™s โ€œCreate Your Own Ringโ€ on the Web. Simply turn off the JavaScript capabilities in your browser and build your ringโ€”with or without the Flash interaction. All customers are equally served.

Problems with AJAX

AJAX poses similar problems to spiders as Flash does. Thatโ€™s because AJAX also relies on JavaScriptโ€”thatโ€™s what the โ€œJโ€ in AJAX stands for, after all (the complete acronym stands for Asynchronous JavaScript and XML). Search engine spiders canโ€™t execute JavaScript commands (or Java either, for that matter). AJAX can be used to pull data seamlessly in the background onto an already loaded Web page, sparing the user from the โ€œclick-and-waitโ€ frustrations associated with more conventional Web sites. Itโ€™s a great timesaver for users, but the additional content thatโ€™s pulled in via AJAX is invisible to the spiders unless itโ€™s preloaded into the pageโ€™s HTML and simply hidden from the user via CSS.

Here, progressive enhancement renders a non-JavaScript version of the AJAX application for spiders and JavaScript-incapable browsers. A low-tech alternative to progressive enhancement is to place an HTML version of your AJAX application within noscript tags (see TheCleanerMovie.com for an example).

Other options include rendering static HTML pages from product searches, as the vertical shopping engine Become.com does. Googleโ€™s guidelines warn that your search result pages must provide value to users to warrant inclusion in its index. So, extra care must be taken if employing this approach.

Widgets, the mini applications webmasters are encouraged to place on their sites to pull data from an external source, are in most cases inaccessible to search engine spiders. Most widgets are built in search engine unfriendly Flash or AJAX.

A well-loved widget in the blogosphere is Eureksterโ€™s โ€œSwicki,โ€ with its โ€œWhatโ€™s Popularโ€ buzzcloud, which you may have seen in the sidebars of popular blogs like TechCrunch. The โ€œWhatโ€™s Popularโ€ buzzcloud. Under our tutelage, Eurekster made its widget more search engine friendly and reaped the benefits with a huge influx of search-referred traffic.

As you head down the road of Web 2.0, just remember that user-friendly doesnโ€™t readily translate into search engine friendly without some assistance. But know that help is available, particularly in the form of progressive enhancement, when you embrace this brave new World Wide Web.