Macs/Apples/THIS HAS EXPIRED
(This is not a spam question or a homework question)
I was wondering would you please explain to me in a simple way that I can understand: wot do I do if a web sites certificate is expired?
Nothing you can do about the certificate. Reputable business usually don't have this problem. Even if this occurs for any reason it's getting fixed within a couple of hours. If the problem occurs for prolonged time that may mean one of the following: lack of tech knowledge/support, out of business sign, fake/phishing website.