a chess term most often related to knights in the center or on the opponent's half of the board, defended by an own pawn, and either no longer attackable by opponent pawns at all, or otherwise, provoking to weaken an opponent pawn on a half-open file no longer "Biting on Granite" .
| The mighty outpost Nd5! 
r4rk1/ppp2ppp/3p2n1/8/4P3/2N5/PPP2PPP/2KRR3 w - -
On a Half-open file
Nimzowitsch defined outposts as squares on a half-open file on the opponent's half of the board, defended by own pawns. The logic between such a placement was to entice the opponent to attack such a piece by a pawn, thereby weakening the pawn standing on that half-open file. In My System knight and rook outposts were mentioned - the former occurred in the center, the latter - on the wing. One game commentary mentions also "a diagonal outpost", though this subject is not expanded.
Some programmers apply a more common meaning of the word outpost, using this term in regard to a strong square in the center or opponent half of the board, defended by own pawn and no longer attackable by the opponent's pawn, occupied or about to be occupied by a knight. In this case the half-open file and provocation aspect of the outpost is lost, though the evaluation term is still useful.
Factors influencing score
To give an estimate of a typical outpost score, Toga log user manual advocates a bonus for a knight outpost on a central square as 10 centipawns, but it is possible to see bonuses as large as 16 centipawns. Furthermore, outpost value can be increased if it is defended by two pawns (thus making exchange sacrifice much less profitable) or if opponent has no minors that he can exchange for an outpost piece.
- knight outposts by Jan K., CCC, August 26, 2004
- Toga Knight Outpost by Ben Tennison, CCC, December 10, 2012 » Toga
- The eternal knight by Lyudmil Tsvetkov, CCC, January 18, 2013
- A question about Outpost Knights / Bishops by Andrew Grant, CCC, May 15, 2016
- Outpost (chess) from Wikipedia
- An Outpost by Iryna Zenyuk, July 16, 2009, Chess.com
- Outpost (disambiguation) from Wikipedia
- Outpost (military) from Wikipedia
- Outpost Islands from Wikipedia