The hashtag is an integral part of Twitter. They made up 40 percent of the trending topics in 2010, they have been used to organize protests, and businesses have found them to be effective marketing tools.

And much to the chagrin of Facebook users who have to read their friend’s Twitter updates, hashtags are a pretty Twitter-specific phenomenon in social media. However, the creator of the hashtag wants to bring them to Google+ – which could spell trouble for Twitter.
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