It has to be posted in 2 visible places in the place of work (typically a bulletin board). I believe the rationale behind this is to allow other employees to as

It has to be posted in 2 visible places in the place of work (typically a bulletin board). I believe the rationale behind this is to allow other employees to ask about applying for the job. As people below mentioned, it is anonymized and typically shows the salary range and the job classification.