Most network adapters have a unique identifier called a Media Access Control address, or more usually a MAC address. It's sometimes useful to identify the MAC addresses of your network equipment, for example if you're filtering access to some resource, but Windows doesn't make this easy. Typically you'll have to use the IPCONFIG /ALL command on each PC in turn, then try to figure out which adapter is which, but this is messy, complicated and doesn't always work.
Find MAC Address is a much simpler solution. Forget command line complexities, just launch the program, click File > Find MAC Address and it'll scan your system, reporting on the MAC addresses of any adapters it finds. You can choose to scan a local or remote computer, a specified range of IP addresses, or your entire network. And four scanning methods are supported - ARP, Netbios, NET API, WMI - so the program should be able to identify MAC addresses on even the most complex of network setups.