Glossary

This glossary contains the definition of common terms used in the Software Heritage project.

C

Content

a file stored in the archive, identified by its cryptographic hashes (SHA1, "git-like" SHA1, SHA256) and its size

Cryptographic hash

(also called Checksum, Digest) a fixed-size "summary" of a stream of bytes, that is easy to compute, and hard to reverse. (Cryptographic hash function Wikipedia article)

D

Directory

a set of named pointers to files, directories and revisions

H

Hash

see Cryptographic hash

O

Origin

(also called Data sources) a location from which a coherent set of sources has been obtained.

Some examples of origins :

• a git repository
• a directory containing tarballs
• the history of a Debian package on snapshot.debian.org.

P

Project

R

Release

a revision that has been marked by a project as noteworthy with a specific, usually mnemonic, name (for instance, a version number).

Some examples of releases :

• a git tag with its name
• a tarball with its name
• a Debian source package with its version number.

Revision

a "point in time" snapshot in the development history of a project.

Some examples of revisions :

• a git commit

S

SHA

(Secure Hash Algorithm) a family of Cryptographic hashes published by the NIST (SHA Wikipedia article)

V

VCS

a Version Control System, like git, subversion or mercurial