Shard is a command-line tool that lets end users check to see if their current password for Facebook, Twitter or other social sharing sites is commonly used on other platforms. Security researcher Philip OKeefe developed the tool after discovering that a randomly generated, eight-character password he used to protect several services was among the 177 million leaked LinkedIn passwords this May. O’Keefes tool taps a huge market: Password problems remain one of the top threat vectors for malicious actors because many employees prefer to use easily guessed, familiar account details across multiple sites.”]
Source: https://securityintelligence.com/news/shard-password-peace-of-mind-or-potential-problem/