PS

PS or ps may stand for:

• postscript (most commonly), a portion of a letter labelled P.S. added after the main body of the letter was written. It stands for post scriptum, a Latin expression meaning "after writing".

• Parti socialiste or Partido Socialista (Socialist Party)
• Pferdestärke -- German for horsepower
• PlayStation
• Political science
• polystyrene, the resin identification code
• PostScript, page description language for computers
• Proton Synchrotron
• Public school in the United States, often as part of the number of an unnamed school, such as P.S. 31.