Rss

Really Simple Syndication (RSS) is used to broadcast changes to a website.
RSS aggregators collect these feeds, and notify you so you do not need to
continuously visit a website to see if there are changes.

RSS Readers/Aggregators

You consume RSS feeds with RSS readers.
You can produce RSS feeds for media that does not support it with RSS aggregators.
See programs: news readers.

RSS Feeds services

Common Feed Links

# very common
domain.com/feed.xml
domain.com/atom.xml

Try view-source on the page, and search rss,
looking for a line like the following.
This is a RSS feed.

<link rel="alternate" type="application/rss+xml" href="https://domain.com/index.xml" title="foo bar baz">

YouTube

https://www.youtube.com/feeds/videos.xml?channel_id=${CHANNEL_ID}    # youtube channel
https://www.youtube.com/feeds/videos.xml?playlist_id=${PLAYLIST_ID}  # youtube playlist

Extract rss feed from youtube channel homepage: https://gist.github.com/tjluoma/fdbc63ceb78a2aecd3d638fd18b6ec6e

Aggregators

You can use rss aggregators as adapters for websites that do not create RSS feeds themselves.
(ex: follow github issues, scientific journals, etc).

Feeds

CVE index

https://nvd.nist.gov/feeds/xml/cve/misc/nvd-rss-analyzed.xml