Country code top-level domain
Cable and Wireless (Ascension Island)
Entities connected with Saint Helena, Ascension and Tristan da Cunha
.ac is the Internet country code top-level domain (ccTLD) for Saint Helena, Ascension and Tristan da Cunha. It is administered by NIC.AC, a subsidiary of the Internet Computer Bureau based in the United Kingdom.
Registration for this domain is open to anyone. The registry accepts registrations of internationalized domain names.
.ac is marketed by some domain-brokers as a domain for the city of Aachen in Germany, using the analogy to the automotive license plate designation ("AC") for the city.
Use as an abbreviation for "academic"
Due to its similarity to the .ac (“academic”) second-level domain that exists under some country code top-level domains, some educational institutions also register under the .ac top-level domain:
Several leading British universities have registered their .ac domain and use this to redirect to their .ac.uk webpages. Examples include: