Aliases

An alias is an alternate name or identity for a person, object, or concept. It can be used to conceal identity, rebrand, or simplify reference. Aliases occur in everyday life (nicknames, pen names), in legal or criminal contexts, and in technical fields where a secondary name serves a particular purpose.

In computing and networking, an alias serves as a stand-in for a primary name. Command aliases in Unix-like shells allow a user to substitute a short command for a longer one. In databases and programming languages, a name can be aliased for readability or scope, such as table or column aliases in SQL with the AS keyword, or type aliases in programming languages. Email systems use alias addresses that forward to one inbox, allowing users to receive mail at multiple addresses. The Domain Name System uses alias concepts via CNAME records to map one domain name to another.

In media and law, aliases frequently denote alternative identities. Individuals may adopt stage names, pen names, or pseudonyms; criminals may use aliases to avoid detection. In literature and reference works, an alias is the "also known as" name for a person, place, or work.

Historically, aliasing is a generic term across disciplines. It is typically defined as any alternate designation that preserves identity while altering how that identity is referenced.