[saisi]

Using Facebook for comparison, a retweet is similar to the 'share' button. Heart parallels the 'like' button. Retweeting explicitly draws your followers' attention to the tweet. While a heart seems to have a multitude of purposes: right from expressing sentiment to bookmarking. Twitter in this case wishes to make it clear to new users that Heart is how they express sentiment. Behaviorally, retweets tend to be expression of public endorsement. While hearts(previously favorites) are a semi-private invocation of approval or interest