A wanted poster was a display of an individual who had committed a crime but had not yet been apprehended. Wanted posters typically displayed a mugshot 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", "Rules of Engagement", "A Time to Stand", "Rocks and Shoals", "Sacrifice of Angels")
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")
Most of the wanted posters seen on Deep Space Nine were make-up continuity photos provided by the make-up department from actors who previously appeared in a Star Trek episode such as Jeffrey Hayenga, Frank Collison, and Norman Large.