Every advertisement has it's application form, than can be used by the candidates to apply to a specific position. The application form is a link, that can be put anywhere - on a job board, on the website, in social media, in e-mail. The candidate that applies, appears in the candidate database in TRAFFIT
Unique link is an application form, that has an additional data attached - the user ID. This way, if the user (recruiter) is sharing the application form, the candidate that applies will be matched in the system as the one, that was acquired by him.
En example of a regular and unique application form link:
If you want your users to be able to generate unique link, check this guide to know ho to do it.