The domain name of a website (for example: "manhattan.edu") is unique to the organization or individual who hosts that website. The top-level section of the domain name (for example: ".edu") will usually depend on the type of organization or the country that is hosting the website.

However, many top-level domains are unrestricted (meaning that they can be used for any type of website). So a website with a ".org" domain is not necessarily a legitimate organization.

There are hundreds of top-level domains. These are the most common ones:

.com	Used for businesses (unrestricted)
.edu	Used for colleges and universities (restricted)
.gov	Used for government entities within the U.S. (restricted)
.mil	Used for military entities within the U.S. (restricted)
.net	Used for network infrastructures (unrestricted)
.org	Used for other types of organizations (unrestricted)