.co (second-level domain) .co (second-level domain) In a number of countries, .co is used as a second-level domain to mean "commercial" and domain registrants register second-level domains of the form .co.xx, where xx is the country code top level domain (e.g., .co.uk in the U.K. and .co.jp in Japan). Some of the countries using .co as a second-level domain include: Barbados (.bb), Cook Islands (.ck), Costa Rica (.cr), India (.in), Indonesia (.id), Israel (.il), Japan (.jp), New Zealand (.nz), South Africa (.za), South Korea (.kr), Thailand (.th) and the United Kingdom (.uk). .co is also a country top-level domain corresponding to Colombia. Its
.si female form). Pepsi also has a pep.si TLD to shorten links. According to research by McAfee performed in 2010, the Slovenian TLD is the tenth most secure. .si .si is the Internet country code top-level domain (ccTLD) for Slovenia. It is administered by the ARNES, the Academic and Research Network of Slovenia. In 2010, the registry has hosted 80,000 domain names. In 2012, that number increased to 100,000 ".si" domain names when the domain "zj.si" was registered by Jasico d.o.o. Domain hacks for the .si TLD are quite popular, since "si" is second person singular of the "to be" verb