[PaulAJ]

If you Google for "what is my ip?" then Google will tell you. If it looks like "12.34.56.78" (known as "dotted quad") then your computer is using IPv4. If it looks like "FE80:0000:0000:0000:0202:B3FF:FE1E:8329" or "FE80::0202:B3FF:FE1E:8329" then you are using IPv6.

[ghshephard]

It's ironic that 12.34.56.78 is known as dotted quad, but www.acme.com 86400 IN AAAA fd::1 is known as a Quad-A.