For example, when speaking, teenagers are more likely to use the phrase 'He was like, 'What's up?'' than 'He said, 'What's up?'' - but the opposite is true when they are instant-messaging. This supports the idea that IM represents a hybrid form of communication.

Nor do teens use abbreviations as much as the stereotype suggests: LOL (laugh out loud), OMG (oh my god) and TTYL (talk to you later) made up just 2.4 percent of the vocabulary of IM conversations - an 'infinitesimally small' proportion, say the researchers.

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