The AP Stylebook has released its new social media guidelines, including the official change from “Web site” to “website” (a move first reported back in April) and 41 other definitions, use cases and rules that journalists should follow.

Among the more interesting changes –- at least from a grammar and style standpoint –- are separating out “smart phone” as two words, hyphenating “e-reader,” and allowing fan, friend and follow to be used both as nouns and verbs.

Beyond that, the AP has also defined a number of acronyms that are commonly used in texting and instant messaging. While most of them should be fairly well-known to regular web and mobile phone users (ROFL, BRB and G2G are among the definitions) one actually was new to me: POS.

According to the AP, this stands for “parent over shoulder” (I’ve used POS to refer to something else occasionally, but I digress), and is used by “teens and children to indicate, in an IM conversation, that a parent is approaching.” Elsewhere, other terms making the cut include “trending,” “retweet” and “unfriend” (“defriend” is also acceptable, though the AP concludes it’s less common).

Finally, the AP also offers some basic rules of thumb for how social media should and shouldn’t be used by journalists, with a focus on making sure they continue to confirm sources and information they find on blogs, tweets and other forms of social media.