What is "pashkvil"

A pashkvil (; pl. pashkvilim פשקווילים) is a broadside or poster that has been situated on a public wall or location in an Orthodox Jewish community, and most commonly within Hareidi enclaves. Pashkvilim are sometimes distributed anonymously; however, many are posted with rabbinic endorsements or the name of an activist group appended to the bottom.