  Pinterest is an image-based online social network, which was launched in the
year 2010 and has gained a lot of traction, ever since. Within 3 years,
Pinterest has attained 48.7 million unique users. This stupendous growth makes
it interesting to study Pinterest, and gives rise to multiple questions about
it's users, and content. We characterized Pinterest on the basis of large scale
crawls of 3.3 million user profiles, and 58.8 million pins. In particular, we
explored various attributes of users, pins, boards, pin sources, and user
locations, in detail and performed topical analysis of user generated textual
content. The characterization revealed most prominent topics among users and
pins, top image sources, and geographical distribution of users on Pinterest.
We then investigated this social network from a privacy and security
standpoint, and found traces of malware in the form of pin sources. Instances
of Personally Identifiable Information (PII) leakage were also discovered in
the form of phone numbers, BBM (Blackberry Messenger) pins, and email
addresses. Further, our analysis demonstrated how Pinterest is a potential
venue for copyright infringement, by showing that almost half of the images
shared on Pinterest go uncredited. To the best of our knowledge, this is the
first attempt to characterize Pinterest at such a large scale.
