XCOPY command, 151, 331–332, 630
Xeon processor, 428
XGA (Extended Graphics Adapter), 496–497, 859
XMA (Extended Memory Specification), 635
XML (Extensible Markup Language), 596
XMODEM method, 477
XMS (Extended Memory Area), 453, 455, 635, 859
XON/XOFF modem flow control, 477