.mo can also refer to the file extension of binary files that have been complied from .po files using GNU gettext.

.mo is the Internet

Internet

The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...

 country code

Country code

Country codes are short alphabetic or numeric geographical codes developed to represent countries and dependent areas, for use in data processing and communications. Several different systems have been developed to do this. The best known of these is ISO 3166-1...

 top-level domain

Top-level domain

A top-level domain is one of the domains at the highest level in the hierarchical Domain Name System of the Internet. The top-level domain names are installed in the root zone of the name space. For all domains in lower levels, it is the last part of the domain name, that is, the last label of a...

 (ccTLD) for Macau

Macau

Macau , also spelled Macao , is, along with Hong Kong, one of the two special administrative regions of the People's Republic of China...

. The inclusion of the letter "o" in the TLD refers to the alternate spelling of Macao.

The registry for this domain name is operated by the Macao Network Information Center (MONIC). Operated by the University of Macau

University of Macau

The University of Macau, ;, established in 1981, was the first and currently the largest university in Macau, a former Portuguese colony. It was formerly known as University of East Asia , and was renamed the University of Macau in 1991. The university offers about 100 Doctoral, Master's and...

 since 1992, MONIC administers the registration of the country-code domain names ccTLD.

To further promote the steady development of services, Macao SAR government

Government of Macau

The Government of the Macau Special Administrative Region of the People's Republic of China , are headed by secretariats or commissioners and report directly to the Chief Executive of Macau. The affairs of the Government are decided by secretaries, who are appointed by the Chief Executive and...

changed the operation entity of MONIC. Effective from 12 March 2011, HNET Asia Limited appointed by the Macao SAR government, is responsible for the operating MONIC.

However, second-level domain is only available for the registrants who has registered a same name at third-level.

.com.mo - commercial entities

.edu.mo - educational institutions

.gov.mo - government departments

.net.mo - network service providers

.org.mo - non-profit organizations