The full form of P.S. is Post Scriptum

Post Scriptum is a WW2 simulation game, focusing on historical accuracy, large scale battles, a difficult learning curve and an intense need for cohesion, communication and teamwork.

Experience a full-scale battlefield with 80-Player Servers, 50+ usable vehicles, Squad roles, Supply runs and Base Building. Post Scriptum is a unique experience, recreating a Historically Accurate, Immersive & Realistic gameplay.

Players will be given the option to fight with the British Airborne Division, British XXX Corps, US 101st / 82nd Airborne Division or several branches of the German Army, such as the Wehrmacht or the Waffen SS. It’s a rare opportunity to experience the intense battlefield that was the Battle of Arnhem, which stretched across farms, woods, villages and city areas. Each area is being accurately recreated from archival references that range from street level to aerial images. Whether you’re jumping out of a plane, resupplying friendlies or operating a tank you will find multiple reasons to drop back into the battlefield in this grand scaled representation of a WW2 setting never explored in a large multiplayer environment.

Post Scriptum offers a full fledged combined-arms experience in a authentic and realistic setting. With this comes the need to work together to take control points and various objectives. You can decide whether you will be in a Infantry, Armoured or Logistic Section, each with their own set of roles and responsibilities. Using in-game voice communications and waypoints, sections can work together to co-ordinate from where to place fortifications, to what sector to attack.

The full form of P.S. is postscript 

A postscript (P.S.) is an afterthought, thought that’s occurring after the letter has been written and signed. The term comes from the Latin post scriptum, an expression meaning “written after” (which may be interpreted in the sense of “that which comes after the writing”).

A postscript may be a sentence, a paragraph, or occasionally many paragraphs added, often hastily and incidentally, after the signature of a letter or (sometimes) the main body of an essay or book. In a book or essay, a more carefully composed addition (e.g., for a second edition) is called an afterword. The word “postscript” has, poetically, been used to refer to any sort of addendum to some main work, even if it is not attached to a main work, as in Søren Kierkegaard’s book titled Concluding Unscientific Postscript.

Sometimes, when additional points are made after the first postscript, abbreviations such as PSS (post-super-scriptum), PPS (postquam-post-scriptum or post-post-scriptum) and PPPS (post-post-post-scriptum), and so on, ad infinitum are used, though only PPS has somewhat common usage.