In a number of countries, the phrase 'trading as' (abbreviated to t/a) is used to designate a trade name. In the United States, the phrase 'doing business as' (abbreviated to DBA, dba, d.b.a. or d/b/a) is used, among others, such as assumed business name or fictitious business name. In Canada, 'operating as' (abbreviated to o/a) and 'trading as' (abbreviated to T/A) are used, although 'doing business as' is also sometimes used.
A company typically uses a trade name to conduct business using a simpler name rather than using their formal and often lengthier name. Trade names are also used when a preferred name cannot be registered, often because it may already be registered or is too similar to a name that is already registered.