File extension
.deb
Debian package
.deb files are Debian software packages: ar archives used by Debian, Ubuntu and derived Linux distributions to distribute installable software.
Known meanings
Formats and reference material for .deb
Debian package
ar-based binary package format used by dpkg and APT
Details
Format notes
DEB
A .deb file is a binary package for the Debian family of Linux distributions,
including Debian, Ubuntu and Linux Mint. Packages are installed with dpkg and
usually managed through apt, which resolves dependencies and downloads packages
from repositories.
Structure
A deb is an ar archive that starts with the text !<arch>. In the current
format it contains three members in a fixed order: debian-binary, a small text
file with the format version (2.0); control.tar with the package metadata
(compressed, for example control.tar.xz or .zst); and data.tar with the
files to install (compressed likewise). The control archive holds the control
file (name, version, architecture, dependencies, maintainer, description),
checksums, and maintainer scripts such as preinst, postinst, prerm and
postrm.
Tooling
dpkg-deb builds and inspects packages, dpkg -i installs them, and ar x can
unpack the outer container for manual inspection. Package contents and metadata
conventions are defined by the Debian Policy Manual. A related extension is
.udeb, used for stripped-down packages in the Debian installer.
Preservation And Security Notes
Maintainer scripts run as root during installation, so only install packages
from trusted sources. Repository metadata is normally signed; individual .deb
files downloaded outside a repository carry no such guarantee unless separately
verified.
Further Reading
- deb(5) manual page:
https://manpages.debian.org/stable/dpkg-dev/deb.5.en.html - Debian Policy Manual:
https://www.debian.org/doc/debian-policy/ - Debian package basics:
https://www.debian.org/doc/manuals/debian-faq/pkg-basics.en.html