Twitter is mostly used for pointless babble and conversations between people, a study shows.

Marketing intelligence firm Pear Analytics found that 40% of the tweets flowing on the site were about someone eating a sandwich or some other "pointless babble," and 37% were parts of conversations.

A distant third were re-tweets, or messages with "pass along value," accounting for 9% of traffic; followed by self promotion, 6%, spam, 4% and news 4%.

The results surprised Pear Analytics, which expected something far different. "We thought the news category would have more weight than dead last, since this seems to be contrary to Twitter's new position of being the premier source of news and events," the report, released Wednesday, said.

Pear Analytics randomly sampled tweets Monday through Friday every 30 minutes for a six-hour period during the day. The company drew its findings from a sample data set of 2,000 tweets.

Pear Analytics did not make any predictions for Twitter usage in the future.

"As Twitter continues to evolve, not only as a brand but from a user's perspective, it is likely that the usage patterns will change," the report said. "We did not predict that conversational (category) would be as high as it was, or that self-promotion was going to be as low as it was."

Companies are experimenting with Twitter as a mechanism for promoting products and services. However, it remains to be seen whether the effort will lead to more sales.

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