A post is a critical structural element of most fence systems. The owner of a fence is legally the individual with the posts on their property line. It is also a social media thing, I think, but I don’t go there anymore, because one time I tweeted too much and it caused a power failure in Finland. I’m still not totally sure how that happened but my parole officer assures me that this is the case.
You caused the blackout in Finland
– My Parole Officer
I’ve also heard that “post” can refer to mail.