Archival research terms
Record—information of permanent and historic value, often in paper-based form (e.g. a letter, photograph, a map), but can also be a CD, a film or a digital file
Item—a single record or many records, e.g. an item may be a single architectural drawing, a 500-page leather-bound book, or a bundle of correspondence (letters, telegrams, reports)
Series—a group of related items created, received, or used in the same activity
Agency—the Government Agency responsible for creating a series. For example, the Department of Education is the Government agency who created a series of School Admission registers for Runcorn State School. An admission register for Runcorn State School would be considered an item within that series.