x = Guns + N + ' + Roses

Is it Guns 'N Roses or Guns N' Roses? You'll find spelled differently all over the web. For instance, iTunes uses the Guns N' Roses format, whereas this article uses the Guns 'N Roses format.

Either way, here is what Wikipedia has to say about using an apostrophe for ommissions...

Apostrophe showing omission

An apostrophe is commonly used to indicate omitted characters:

It is used in contractions, such as can't from cannot, it's from it is or it has, and I'll from I will or I shall.

The word fo'c's'le is notable in English for having three apostrophes; the alternative spelling without omissions is “forecastle”.

It is used in abbreviations, as gov't for government, or '70s for 1970s. In modern usage, apostrophes are generally omitted when letters are removed from the start of a word. For example, it is not common to write 'bus (for omnibus), 'phone (telephone), 'net (Internet). However, if the shortening is unusual, dialectal or archaic, the apostrophe may still be used to mark it (e.g., 'bout for about, 'less for unless, 'twas for it was). Sometimes a misunderstanding of the original form of a word results in an incorrect contraction. A common example: 'til for until, though till is in fact the original form, and until is derived from it.

It is sometimes used when the normal form of an inflection seems awkward or unnatural; for example, KO'd rather than KOed (where KO is used as a verb meaning “to knock out”), or n'th (an unspecified ordinal) rather than nth.

In certain colloquial contexts an apostrophe's function as possessive or contractive can depend on other punctuation.

We rehearsed for Friday's opening night. (We rehearsed for the opening night on Friday.)

We rehearsed, for Friday's opening night. (We rehearsed because Friday is opening night.)

By the way, Wikipedia follows the Guns N' Roses format. If I were being really technical about this, I would say that Guns 'N' Roses is the proper format.

Check out this Sun Microsystems blog entry for more.