If you have been paying attention while visiting certain websites recently you may have noticed a plethora of pictorial icons at the bottom of the page.
There's a little alien-looking figure, a symbol featuring the letters SU against a blue background and another logo resembling a twig or leaf.
Depending on which site you are visiting, you will see at least three of them. Try any story on http://news.bbc.co.uk and you will find five. Go to the Los Angeles Times (www.latimes.com) and the number rises to eight.
The most I have found is 11 - the New York Observer (www.observer.com). Welcome - if you have never entered it before - to the world of the chicklet.
They appear mainly on web pages featuring interesting content, which is why you'll find them on many news sites.
They turn up often on video sites like Break (www.break.com) as well. And their purpose is to allow you to share your favourite online content with others.
Still using your browser bookmarks to remind you of your most visited sites? That's so last century.
In the ultra networked world of 2007, you need to label, mark and share the best content.
If you think this is a subject for the MySpace generation, you're wrong.
Even if you never use a chicklet or the sites they link to, you'd be mad not to learn something about their existence because they are one of the most effective methods in the world to spread the news about a company, product or service.
None other than the American space agency NASA (www.nasa. gov) has recently relaunched its site to take account of them. The new NASA home page is packed full of opportunities to bookmark, share and reorganise the material according to your own personal preferences.
But before we move on to why NASA has joined this bandwagon, let me introduce you to some of the main purveyors of chicklets.
The best known is Digg (www. digg.com). It is the darling of the web forums and the subject of the kind of buzz that surrounded MySpace about a year ago - largely because its founder Kevin Rose (http://en.wikipedia.org/ wiki/Kevin_Rose), is not exactly publicity-shy.
What Digg does is to allow its members to vote on its content. In other words, if a story appears in the LA Times and 500 people click the little Digg icon beside it, the likelihood is it will appear on Digg's home page as one of the most popular items of the day, week or even month.
Although all the social bookmarking sites operate in slightly different ways, they are all designed to spread information from one user to another.
Other popular examples are Del.icio.us (http://del.icio.us) and Stumble Upon (www.stumbleupon.com).
The latter is the owner of the little blue SU icon I mentioned. Reddit (http://reddit.com) is the little alien I referred to, while Newsvine (www.newsvine.com) is the twig.
To give an example of the power of these sites, I can tell you that as I'm writing this, one of the most popular items on Digg is a feature on how to impress your friends with nine simple tricks of mental arithmetic.
But the subject matter is, in a sense, irrelevant. What's important is that its 389 Diggs (as recommendations on Digg are known) have propelled it on to the front page. Click on the story and you are taken to the site where it first appeared - http://wildaboutmath.com.
Until seeing the item on Digg, I had never heard of the site.
Even the search engines are catching on.
Google's Experimental (www.google.com/experimental) has been trying out a feature that allows you to re-order a search to bring your favourite sites closer to the top.
I'd better mention the other side of the coin briefly.
When Gamespot (www.game spot.com) fired one of its staff, the news was all over Digg's front page in hours, doing some damage to its brand.
In social bookmarking, nothing is kept secret for long.
Bill Law has 30 years' experience in IT, and works in the industry for Fujitsu Services in Northern Ireland. The opinions expressed are his own and not necessarily those of Fujitsu Services. He can be contacted at Bill.H.Law@uk.fujitsu.com.