task of filling up the blanks I'd rather leave to you. Some fields have their own specific placeholder terminology. For example, "widget" in economics, engineering and electronics, or "Blackacre" and "John Doe" or "Jane Doe" in law. "X-ray" was originally a placeholder name for an unexplained phenomenon. Companies and organizations "Ace" and "Acme" were popular in company names as positioning words in alphabetical directories. They were generic, laudatory of whatever products they were used to promote and appeared at the beginning of most alpha-sorted lists. ("Acme" is a regular English word from the Ancient Greek , meaning summit, highest point, extremity or peak, and thus sometimes used for "best".) A well-known example of "Acme" as a placeholder name is the Acme Corporation whose products are often seen in the Wile E. Coyote and the Road Runner cartoons. "Mom and Pop" (in the United States) are occasional placeholders for the individual owners of a generic small family-owned business High Street (UK) or Main Street (US) for the business district of a small town or village, often contrasted as a commercial business entity against Threadneedle Street, City of London in the UK or Wall Street, New York City in America. "Advent corporation" is a term used by lawyers to describe an as yet unnamed corporation, while legal incorporation documents are being prepared. In the case of Advent Corporation, founder Henry Kloss decided to adopt this placeholder name as the formal legal name of his new company. "NewCo" or "Newco" is used in a similar way in the UK for an as-yet-unnamed company. Fictional brands such as Morley are often used in television and cinema as placeholders to avoid unintended product placement. "Brand X" has been used in television advertisements as a generic brand representing any other brand than the one being advertised. "XYZ Widget Company" has long been used in business and economics textbooks as a sample company. Also used as engraving text example on items such as plaques, trophy plates, etc. Occasionally appears on customizable promotional materials including stationery templates, business cards, advertising signage, cups, backpacks, and other "swag" samples. "Contoso" and previously "Northwind" are used as fictional businesses in Microsoft's training materials and documentation. "Oceanic Airlines" is used as a fictional airline in several films, TV programmes, and comic books, typically when it is involved in a disaster or another event with which actual airlines would prefer not to be