How to Recognise an affiliate program

This is something I've always struggled with. I look at landing pages backlinks and I kind of know some links may be affiliate, but how to make sure of that and how do you understand which affiliate program they are using?

Example:https://guitarblog.info/?s=robbie+williams&post_type=product

IS that an affiliate link?Of which network? The shop linked doesn't return any result if I search for "shop" affiliate program

the s tag in the URL usually stands for search. Usual aff links have either aff= or ref= or whatever, but those are all editable by who is in charge of the affiliate program so just by the link you will usually have a hard time finding out if that is an aff program or not. They can also cloak the links so you will have no idea if it's an aff program or not. Best bet is to search for the product along with "Affiliate program" and hope that the program is public