The terms Deep Web, Deep Net, Invisible Web, or Dark Web refer to the content on the World Wide Web that is not indexed by standard search engines. The deepest layers of the Deep Web, a segment known as the Dark Web, contain content that has been intentionally concealed including illegal and anti-social information. The conventional Surface Web was discovered to be too risky for anonymity-seeking terrorists: they could be monitored, traced, and found. In contrast, on the Dark Web, decentralized and anonymous networks aid in evading arrest and the closure of these terrorist platforms. This paper reports some of the recent trends in terrorist use of the Dark Web for communication, fundraising, storing information and online material.