A pawnless chess endgame is a chess endgame in which only a few pieces remain, and no pawns. The basic checkmates are types of pawnless endgames. Endgames without pawns do not occur very often in practice except for the basic checkmates of king and queen versus king, king and rook versus king, and queen versus rook. Other cases that occur occasionally are (1) a rook and versus a rook and (2) a rook versus a minor piece, especially if the minor piece is a bishop. The study of some pawnless endgames goes back centuries by players such as François-André Danican Philidor (1726–1795) and Domenico Lorenzo Ponziani (1719–1796). On the other hand, many of the details and recent results are due to the construction of endgame tablebases. Grandmaster John Nunn wrote a book (Secrets of Pawnless Endings) summarizing the research of endgame tablebases for several types of pawnless endings. The assessment of endgame positions assumes optimal play by both sides. In some cases, one side of these endgames can ; in other cases, the game is a draw (i.e. a book draw). Terminology are queens and rooks. are knights and bishops. A is a row of squares on the chessboard. A is a column of squares on the board. If a player has two bishops, they are assumed to be on opposite colors unless stated otherwise. When the number of moves to win is specified, optimal play by both sides is assumed. The number of moves given to win is until either checkmate or the position is converted to a simpler position that is known to be a win. For example, with a queen versus a rook, that would be until either checkmate or the rook is , resulting in a position that leads to an elementary checkmate. Basic checkmates Checkmate can be forced against a lone king with a king plus (1) a queen, (2) a rook, (3) two bishops, or (4) a bishop and a knight (see Bishop and knight checkmate). See Checkmate for more details. Checkmate is possible with two knights, but it cannot be forced. (See Two knights endgame.) Queen versus rook A queen wins against a lone rook, unless there is an immediate draw by stalemate or due to perpetual check (or if the rook or king can immediately capture the queen). In 1895, Edward Freeborough edited an entire 130-page book of analysis of this endgame,