+++
date    = "2022-05-21T02:49:14+00:00"
lastmod = "2022-05-21T02:49:14+00:00"
tags    = [ "web" ]
author  = "tdro"
+++

The {{< abbr GUID "Globally Unique Identifier" >}} is an interesting element in
the {{< abbr RSS "Really Simple Syndication" >}} specification --- yeah another
post about [`RSS`](https://www.rssboard.org/rss-specification#whatIsRss). You
could hash the content of a post and commit to the idea that it shouldn't
change.

If a post changes, then the `GUID` would provide a trail of edits, with the
drawback of possibly resurfacing an old post. This
[article from 15 years ago](http://www.xn--8ws00zhy3a.com/blog/2006/08/rss-dup-detection)
explores what feed readers did at the time when given a `link` and/or `guid`.