I subscribe to the Associated Press Stylebook online. For $20 a year, you can’t beat it for an instantly accessible, continually updated resource. And they send out periodic email updates with new items, clarifications and pronunciation guides that constitute a kind of meta look back at recent headlines, politics and trends. Here are some true-to-type examples from today’s update.

If enough reporters repeatedly make grammatical mistakes that drive editors crazy, it merits an entry: a, an — The update adds the word homage: Use the article an before vowel sounds: an energy crisis, an honorable man, an homage (the h is silent), an NBA record (sounds like it begins with the letter e), an 1890s celebration.

This is an example of how the AP has become more sensitive to the vagaries of electronic news: company names — The updated entry includes this wording: You must include the full company name somewhere in the story. This ensures that the story will be among the search results on Yahoo and other websites. Without the full company name, the story may get overlooked.

With all the Wall Street reportage and the economic crises everywhere, this one was inevitable: Dow Jones industrial average — The market indicator comprises 30 leading U.S. stocks. Executives of Dow Jones Indexes choose the companies in the average. Always use the full name on first reference in stories. On subsequent references, use the Dow.

It’s pretty clear why this clarification was needed: illegal immigrant — Used to describe someone who has entered a country illegally or who resides in a country in criminal or civil violation of immigration law. Acceptable variations include living in the country without legal permission. Use of these terms, as with any terms implying illegalities, must be based on reliable information about a person’s true status. Unless quoting someone, AP does not use the terms illegal alien, an illegal , illegals or the term undocumented.

Sometimes the AP offers interesting insights into other cultures: Korean names — The style and spelling of names in North Korea and South Korea follow each government’s standard policy for transliterations unless the subject has a personal preference. North Korean names are written as three separate words, each starting with a capital letter: Kim Jong Il. Use Kim on second reference. South Korean names are written as two names, with the given name hyphenated and a lowercase letter after the hyphen: Lee Myung-bak. Use Lee on second reference. In both Koreas, the family name comes first.

And we thought all that separated them was a demilitarized zone.

Political campaigns always seem to generate a few new entries: PAC — Abbreviation for political action committee. Raises money and makes contributions to campaigns of political candidates or parties. At the federal level, contribution amounts are limited by law and may not come from corporations or labor unions. Enforcement overseen by the Federal Election Commission. PAC acceptable on first reference, spell out in body of story. A super Pac is a political action committee that may raise and spend unlimited amounts of money, including from corporations and unions, to campaign independently for candidates for federal office. Its activities must be reported to Federal Election Commission, but are not otherwise regulated if not coordinated with the candidate or campaign.

Here again, cultural sensitivity rears its ugly head in the second sentence: Ramadan — The Muslim holy month, marked by daily fasting from dawn to sunset, ending with the Islamic holiday of Eid al-Fitr. Avoid using holiday on second reference.

The stodgy Associated Press has been around since the 1920s, but it is attuned to pop culture, hence: shoutout.

And, new to the Pronunciation Guide are: Anwar al-Awlaki — U.S.-born cleric who was key al-Qaida figure; killed in Yemen in 2011 (ahn-WAHR’ al-aw-LAH’-kee), and Ercis — Turkish city damaged in October 2011 earthquake (EHR’-jihsh).