url shorteners

On the short-messaging service Twitter, space is at a premium: You've got 140 characters to make your point, and you probably don't want to waste half of it on a super-sized link to your latest YouTube obsession.

There's an increasingly popular quick fix: a free URL shortener. On one of these Web sites, you can plug in a long Internet address, known as a URL, and it will assign you a much shorter one that is easier to post in e-mails, on Twitter, Facebook or anywhere else. Some link-shrinkers let you personalize the new address with a unique phrase such as your name, or show you how many people click the link after you've posted it.

URL shorteners have been around for several years to offer alternatives to long Web links that were too unwieldy to paste into e-mails. Perhaps the oldest and most popular is TinyURL, a free service started in 2002 by Kevin Gilbertson, a unicycle enthusiast from Blaine, Minn., who was tired of seeing URLs get split up in e-mails related to his online unicycle forum.

Now the rise of Twitter and other social Web sites that encourage users to share small bursts of information has spawned several TinyURL followers, whose names run the gamut from the very short — tr.im — to the not long — notlong.com.

Twitter has directly contributed to the prominence of two services in particular: TinyURL and bit.ly, which began in July as a project at New York-based Web media incubator and Twitter stakeholder Betaworks.

Until recently, Twitter automatically shrank lengthy links by running them through TinyURL. But this spring Twitter switched its default link shortener to bit.ly after finding TinyURL unreliable, said Alex Payne, one of Twitter's lead engineers. (Gilbertson said Twitter didn't contact him about the issues or the change.)

Bit.ly is seeing growth that Betaworks Chief Executive John Borthwick called "pretty amazing." About 100 million bit.ly URLs are clicked on per week.