At the most basic level, archives are collections of information that record an activity of some kind. They can come in almost any format, such as letters, reports, minutes, registers, maps, photographs and films, digital files and sound recordings. Archives can be created by official bodies such as governments, businesses or professional organizations, or equally by individuals. Archives can contain records with a local focus, or specialise in a particular subject or theme: politics, social movements, women's studies, Arab and Islamic studies. Equally, archives created by individuals can range from those of a well-known public figure to an individual's collection of family letters, photographs and memorabilia.
The University of Exeter holds more than 400 archives, including literary, historical and political papers. 
These include a rich collection of twentieth century literary papers by writers associated with the South West of England.
You can find out more by browsing the Collection Highlights on our webpages.
Catalogues for archives are generally arranged differently from catalogues for books. The arrangement is known as a hierarchical arrangement and is created to reflect, as closely as possible, the way an archive was created, or accumulated.
An archive catalogue contains different levels of description beginning with the fonds, or collection level. This top level description provides a broad overview of the archive as a whole, including its size, information on the origin of the collection and the creator, a date range, and information on catalogues or guides associated with the archive - often known as finding aids. It may also tell you whether the archive is available for consultation or not - open or closed. The catalogue is then arranged in sections from largest [collection/fonds] to smallest [items], as shown below.
Published content offered by a library is generally a secondary source of information, for example a monograph, biography, or journal article that has used primary sources within the author's research but which presents a thesis. Secondary sources can also include accounts of historical events created many years after the event has happened. The records in an archive, however, are primary sources and provide first-hand information or evidence relating to historical events or figures. - see our Libguide on Primary Sources.
Published books, whether in physical or digital format, are indexed and catalogued by subject and author, whereas information in archives is arranged according to the person or organization that created it. The archives of two organizations or two different people, should generally be kept separately (unless there is a specific reason for keeping them together, for example the records of a business that included historical records of businesses it took over). This means that you will probably need to look at records from more than one source, or more than one archive, as you gather information for your research.