add note on reliability categories

README.md

@@ -78,7 +78,9 @@ Distribution:
 
 ![Domain Distribution](https://cdn-uploads.huggingface.co/production/uploads/681e3663829118a837bbaeb3/ha-Wn2jgyfBBNG1BeojSH.png)
 
-These are the 5 largest categories; the full list can be found at the bottom of the dataset card
+These are the 5 largest categories; the full list can be found at the bottom of the dataset card. 
+Within each category, the labels usually contain a flag related to reliability (e.g., within 'political', a domain can for example be labelled 'fake news' 
+or 'fact-checker'; within 'phishing', either 'pishing' or 'not'.)
 
 | Domain / area            | Count |
 |---------------------------|--------------|