The Full Authority Files are the entire list of Authority Files, including all see and see also references.
The Full Authority Files may be useful for schools whose library systems contain a significant number of records which have not been downloaded from SCIS, or which regularly undertake a certain amount of original cataloguing. The Full Authority Files allow you to use the list of authorised headings in your library system to ensure consistency with headings across your different types of catalogue records.
The Reference Only Authority Files are a subset of the Full Authority Files that only include headings that have references to each other. In this case, the Authority Files for subject, name and series headings will exclude terms that do not include references to broader, narrower, or otherwise unrelated terms.
If most of your catalogue records are sourced from SCIS and you do little or no original cataloguing, you may choose to download the Reference Only Authority Files.
Your library system vendor should also be able to provide you with further information about whether Full or Reference Only Authority Files are preferable for your library system.