digests

Digests are condensed forms of information that present the essential points of a larger source. The term is used across several fields to refer to summaries, condensed content, or compact representations.

In publishing, digests collect and present shorter versions of longer works. Reader's Digest is a famous example; historically, digest magazines reprint articles and stories in abridged form to fit a compact size and broad audience.

In computing and information security, a digest is the fixed-length output of a hash or message-digest function. Hash digests such as MD5 or SHA-256 are used to verify data integrity, enable digital signatures, or store passwords in a way that protects the original data. They are designed to be deterministic and, ideally, collision-resistant, though some older algorithms have vulnerabilities.

Digests are also used to summarize multiple messages in a single communication, such as a daily or weekly email digest for mailing lists or news services. These digests present highlights or summaries rather than full content to reduce bandwidth and clutter.

In information systems and content syndication, a digest can refer to a summary of recently published items or a compact feed that allows users to preview content before accessing full articles. The term thus encompasses both textual summaries and compact data representations used to convey information efficiently.