The internet is a place jam-packed with digital stuff. Not everything on the web is a "website".
We usually use "website" to mean a group of pages linked by design and navigation, owned and created by one entity.
Within websites, various documents might be included.
- news stories
- advertisements
- knowledge base
- blog
- media
- about (self-description), information about the entity
- research or published works
- store/sales
When you do a search, you might be accessing a document within a larger site. It's important to recognize:
- What is the document I'm looking at?
- Who posted it online? Is it within a larger website?
- How does it fit within the larger website?
You will need to know this information to be able to properly cite any web source.