HTTP/HTTPS/WireShark Questions

These questions popped into my brain earlier. I did a google search, but some answers weren't there, and others I couldn't understand.

• On sites without HTTPS or HTTP, and just starts with "www", are they still HTTP sites? And I know HTTPS says "Secure" so traffic should be encrypted. But then does that mean HTTP sends un-encrypted traffic?

• Where can I find a key to the types of packets displayed using WireShark?

• How can I filter IPs to where I only want the capture of packets between my device and the site it is connecting to? (I tried to do ip==(my internal ip)&destination==(IP of the site) but that doesn't work)

• Does WireShark only work on internal IPs? (I don't plan on capturing anyone else's traffic, this question is just more on the curiosity side)

• For some reason, sometimes, when I ping a site, it sometimes gives me (currently using letters to represent the numbers) A.B.C.D, but if I wait a while and ping it again (a few minutes later, not spam-ping-ing it) i get W.X.Y.Z

Why does the IP change even though the website is the same?

• Lets say I login to my account on that website, how can I see my own password in plain text?

Disclaimer: That said website is one that I help administrate/Moderate on.

Thanks