Q. What is an archive? What is a special collection?
I don't know what "archives" and "special collections" mean.
archives (lower case)
refer to permanently valuable records. Unlike libraries, archival collections are mostly unpublished materials and often these materials are rare or unique. Archives do not circulate (cannot be checked out) because their rare and unique characteristics classify them as having enduring value and warrant preservation for both current and future researchers (several generations if not longer).
An Archives or Archive
is the organization preserving the documents and records of a particular group. For example:
CSUDH University Archives includes historical records of the University.
CSUDH's Archives & Special Collections department also preserves manuscript collections in our archive of historical materials of local and state communities.