Editorial Style Guide

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(Laurie Smith-Frailey)

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U.S. (adj.)

Unlike most acronyms and abbreviations, U.S. takes periods—with no spaces in between. When it stands alone, United States should be written out.

  • I live in the United States.
  • I am a U.S. citizen.

UN, United Nations

No periods in the abbreviation.

under way (adv.)

Two words. Do not use underway.

Unix, UNIX

When referring to the computer operating system, use Unix (initial capital only). When referring to the specific software product used with Unix, use UNIX (all caps).

Factoid: Surprisingly, at least one source says that UNIX is actually not an acronym at all; instead, it’s a pun on Multics, the earlier operating system from which Unix sprang.

until, till

See Troublesome pairs.

up-to-date (adj.)

Hyphenate in all cases.

  • The filing is completely up-to-date.
  • The most up-to-date information on school closings can be found on the radio station’s Web site.


One word. Means to transfer a file from a personal computer to a server, to a network, or to the Internet.

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upper class (n.); upper-class (adj.)

  • The upper classes in the boarding school sometimes enjoy special privileges.
  • It was intended to be strictly an upper-class party.


One word. Means formatted in capital letters.


Use with caution, as this term is both vague and gender-biased. It is intended to refer to students in the junior or senior class of a secondary school or college/university. To be more specific, use juniors and seniors or third- and fourth-year students. To avoid the gender gaffe without specificity, use upper-class students.


URL stands for uniform resource locator—better known as an Internet address.

The URL consists of three parts: a protocol (usually http://); a directory path consisting of folder names separated by forward slashes (“/”); and sometimes a specific filename.

The http:// portion of the URL should not be omitted unless absolutely too cumbersome! Always use a forward slash after folders/directories, and provide a full file name with extension for specific pages. Filenames usually end in “.html” or “.htm.”

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Stands for Undergraduate Research Opportunities Program. Note the word “Opportunities”, not “Opportunity.” See Acronyms.


Stands for Undergraduate Practice Opportunities Program. Again, note the word “Opportunities”, not “Opportunity.” See Acronyms.

use to, used to

See Troublesome pairs.

user ID, username

Means the name by which a user is identified on a computer or network. Note that username is one word, user ID is two.


Hyphenate in all uses.

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