"Subscribed Thread" ?????

[BillyMac]

From JRutledge: "Newer people do not know how to use the search feature"

I don't consider myself to be a new person, and I do know how to use the search feature, however, I'm sure that there are features that I either don't know about, or don't know how to use, because I do not consider myself to be very computer literate, for example, I have no idea what a "subscribed thread" is. Could someone please explain this to me? I know nothing about this feature.