A couple of things that page doesn't get quite right: > Mr., Mrs., and Ms. all take periods in American English. In British English, the periods are omitted.

A couple of things that page doesn't get quite right: > Mr., Mrs., and Ms. all take periods in American English. In British English, the periods are omitted. Common British practice omits full stops after any abbreviation (not just these three titles) where the last letter is the same as the last letter of the unabbreviated word: so Dr, Lt, hr aren't followed by full stops but Prof., Capt., sec. are. In fact it's becoming more and more common to omit full stops after abbreviations entirely: this is the Guardian's house style, for example. > British usage dictates a period between the hours and minutes when writing the time (e.g., 10.30). American usage dictates a colon (e.g., 10:30). Usage varies, but a colon is far more common with the 24-hour clock (e.g. 15:00 rather than 15.00).