Is it better to write without contractions? E.g. "cannot" instead of "can't"

Question

Possible Duplicate:
Using contracted forms (“don't”, “let's”) in a formal text
Usage of contractions like “it's” and “that's” in textbooks
Should contractions be avoided in formal emails?
Are contractions like “didn't” forbidden in written English?

Is a text written without abbreviations generally considered more refined, well-mannered and couth? For some reason, I have gotten that impression. E.g.

• "It's warm out, isn't it?" vs "It is warm out, is it not?"
• "I can't say" vs "I cannot say"

Are there situations when abbreviations like these should be avoided? What is the popular consensus about their usage?

Answer 1

Those are not abbreviations but contractions. If the text is reporting dialogue, then it's usual to use them. Whether a writer uses contractions otherwise depends on the context. They perhaps appear more frequently in informal than formal writing. However, Pam Peters in her entry on contractions in 'The Cambridge Guide to English Usage' writes, with her customary good sense :

The writers of formal documents may feel that they undermine the authority and dignity of their words. But the interactive quality of contractions lend to a style is these days often sought, in business and elsewhere. They facilitate reading by reducing the space taken up by predictable elements of the verb phrase, and help to establish the underlying rhythms of prose.