IP trunk Online vs registrations

Hi need some help to understand those 2 values displayed in the freepbx system status:

Ip trunk Inline versus Ip trunk registrations.

Thanks.

Trunks online indicates that the trunk (assuming it has qualify set) is able to reach the peer and exchange a SIP message, it does not indicate that the parameters are correct or any type of sanity check.

registrations indicates the number of valid entries in the SIP and IAX registry.