Changes

[[File:machackdisplay02.jpg|border|right|thumb| Mac Hack [[Lawrence J. Krakauer#DEC340|display]] <ref>[http://ljkrakauer.com/LJK/60s/resign.htm I resign] by [[Lawrence J. Krakauer]]</ref> <ref>[http://ljkrakauer.com/LJK/60s/chess1.htm Chess stories] by [[Lawrence J. Krakauer]]</ref> <ref>see also [http://projects.csail.mit.edu/video/history/aifilms/63-chess.mp4 63-chess.mp4] hosted by [https://www.csail.mit.edu/ MIT CSAIL]</ref>]]

a user interface where [https://en.wikipedia.org/wiki/Interaction interaction] between user and a (chess) program takes place. Opposed to the sequential nature of a pure text based [[CLI|command-line interface]], where a program prints its output and prompts for input, a [https://en.wikipedia.org/wiki/Graphical_user_interface graphical user interface] allows a more sophisticated, graphical presentation of the programs output, as well within its [https://en.wikipedia.org/wiki/Event-driven_architecture event-driven architecture] a more flexible user interaction not only by typing text commands, but using a [https://en.wikipedia.org/wiki/Pointing_device pointingdevice], a [https://en.wikipedia.org/wiki/Mouse_%28computing%29 mouse] or a pen or finger pointing on and touching a [https://en.wikipedia.org/wiki/Graphics_tablet graphics tablet] with its [https://en.wikipedia.org/wiki/Touchscreen touchscreen], for random and [https://en.wikipedia.org/wiki/Direct_manipulation direct manipulation] of graphical elements. A GUI dedicated to play chess typically has a graphical [[Chessboard|board]] and [[Chess Game|game]] representation, where the user may [[Entering Moves|enter moves]] by [https://en.wikipedia.org/wiki/Point-and-click clicking] and [https://en.wikipedia.org/wiki/Drag-and-drop dragging] a piece, quite similar to moving a piece on a "real" chess board.