The 'iw phy' command in Linux is used to display detailed information about the hardware and PHY capabilities of a wireless adapter. It provides comprehensive details including channel widths, output power settings, and supported channels. On the other hand, 'ifconfig' and 'iwconfig' are more commonly used for managing network interfaces and wireless connections rather than displaying detailed hardware capabilities. 'netsh wlan show device' is a Windows command, not applicable to Linux.