Subdomain

As a technical subdomain of biology ecological investigations have evolved from what has been traditionally called natural history.

A domain is a subdomain of another domain if it is contained within that domain. This relationship can be tested by seeing if the subdomain's name ends with the containing domain's name. For example, A.B.C.D is a subdomain of B.C.D, C.D, D, and " ".

BIND 9 Administrator Reference Manual (9.3.2), Copyright © 2004, 2005 Internet Systems Consortium, Inc. ("ISC"), Copyright © 2000-2003 Internet Software Consortium, https://web.archive.org/web/20060619063455/http://www.bind9.net/manual/bind/9.3.2/Bv9ARM.ch01.html Every name in the DNS tree is a domain, even if it is terminal, that is, has no subdomains. Every subdomain is a domain and every domain except the root is also a subdomain.

"We hope that the parties responsible for managing the security of this subdomain will take this as a wake-up call, and not as a threat," a note on the page said.

On July 8, 2025 Glitch project hosting and user profiles will be shut down. Your Glitch dashboard will remain available as usual through the end of 2025, with access to download all of your code for your projects, as well as a new feature to set up redirects for your project subdomains so your URLs keep working.

In en.wiktionary.org, en is a subdomain.