A wanted poster was a display of an individual who had committed a crime but had not yet been apprehended. Wanted posters typically displayed an image of the criminal and the crime they committed. Depending on the source they sometimes offered a warning or monetary reward.
A number of wanted posters were displayed in Constable Odo's security office aboard Deep Space 9. (DS9: "Captive Pursuit", "Q-Less", "Dax", "Vortex", "If Wishes Were Horses", "The Forsaken", "Dramatis Personae", "Duet", "In the Hands of the Prophets", , "The Circle", "The Siege", "Necessary Evil", "Second Sight", "Sanctuary")
Nog was familiar enough with the posters in Odo's security office to recognize when a new one was posted. In 2370, he took note of Plix Tixiplik's poster after being hauled off by the constable. (DS9: "Sanctuary")