The Acer NDIS WAN Miniport Adapter is a network device driver used by Acer computers, typically for connecting to wide-area networks (WANs) such as those provided by cellular modems or VPN connections. "NDIS" stands for Network Driver Interface Specification, and the term "Miniport Adapter" refers to the interface between the operating system and the hardware that handles network connections. In this case, the driver supports network devices that connect to the Internet or other remote networks through technologies like mobile broadband, Ethernet, or VPN.