On Wednesday, companies and organizations can register Web addresses with a new top-level domain, .tel. The new domain, which stores and encrypts contact information directly into the Domain Name System, has the potential to become a phone book for the Internet.

A .tel domain name links to the contact information of businesses, organizations and individuals. Information can include telephone numbers; links to Web sites, including a Facebook or MySpace page; e-mail addresses; instant messaging names, and, if you wish, identities for virtual games such as Xbox Live or Second Life.

Because the data is stored in the DNS, rather than on a server, when a person updates a phone number or address using their .tel account, it is automatically updated in the address books of their friends who have their .tel information stored on a smartphone or other mobile device.

“There is nothing else like this on the Web,” said Mr. Mansell. Rather than sending a note out to all of your contacts, like some contact management services, the update is seamless.

Individuals can also choose to display their location, allowing their contacts to see where they are at any given time and opening the door for location-based services.

The initial registration period is open only to businesses and organizations with trademarked names that want to secure the related .tel address for a fee of about $400 a year (that’s what DomainMonster charges, but prices will vary by registrar). A “land rush” period, in which anyone can buy domain names for around $150 a year, begins Feb. 3. After March 24, domain names will be available for around $20 a year.