They're talking about
the outland application package. There are three sections to the application - Part 1 is the sponsor's application forms and the checklist that tells you what supporting documents and evidence you need to submit, and Parts 2 & 3 are the Applicant's forms. The "idea" is that if your partner is overseas, you will be sending Parts 2 & 3 to them to fill out, and they will return their application forms and all the supporting documentation and evidence listed in their document checklist (Appendix A of Part 3) to you. You submit the entire package to the Case Processing Centre in Mississauga, where they assess your eligibility to sponsor. If you're approved, CPC-M transfers the entire application package back to the overseas visa office that represents your partner's country of birth or permanent status and that office finalizes the application.
If your overseas partner has internet access, it's easier for them to just pull up the forms from the link posted above and print them out. They can even type their information into the forms before printing - then collect all their supplemental information, get their medical exam and criminal clearance(s) done, and send the package back to you to combine with your Part 1.
