Archives may be selected for preservation for many reasons. Some are selected because they are essential for understanding the history of an individual, family or organisation. Others may prove a person's rights or entitlements.

The word 'archives' covers a wide variety of records, including files created by individuals, an organisation or government, such as diaries, letters, maps, photographs, sound recording, moving images and objects. As people and organisations increasingly use computers to do business, archives can also include emails, word processed documents and other digital content.