The official Debian distribution now ships on 9 to 10 binary DVDs or 75 to 85 binary CDs (depending on the architecture) and 10 source DVDs or 59 source CDs. Additionally, there is a multi-arch DVD, with a subset of the release for the amd64 and i386 architectures, along with the source code. Debian is also released as Blu-ray (BD) images, 2 each for the amd64 and i386 architectures, or 2 for the source code. For size reasons, some very large packages are omitted from the CD builds; these packages fit better in the DVD and BD builds, so are still included there.

Being upgraded to version 3.14, the new GNOME desktop brings many new features and usability improvements.

The design of the GNOME shell has been updated. The bottom message tray is larger, easier to use and less prone to appear accidentally. A new system status area in the upper right corner puts all useful settings in the same place.

The screensaver has been replaced by a "lock screen" that still brings minimal functionality when the user is away. For example, you can pause the music, be informed of a new e-mail, or change the screen brightness, all of that without entering a password. Pressing the Escape key or starting to type the password brings back the login prompt. The GNOME display manager uses the exact same design for consistency.

Several applications, including the Nautilus file manager, the gedit text editor, and the evince document viewer have seen their design made much more compact, merging the window titlebar with the toolbar. This leaves much more room for the documents the user is working on. The standard dialog boxes have undergone similar changes.

Support for touch screens has been fully integrated, including intuitive gestures based on multiple finger movements. GNOME now also supports high resolution (HiDPI) screens, taking full advantage of fine pixeling for the clearest rendering.

GNOME supports geolocation, and includes a smooth mapping and navigation application.

The user documentation is much more complete, and includes video tutorials for new users.

More information can be found in the GNOME 3.14 release notes.

Introduced in Debian 7, systemd is now the default init system. It provides advanced monitoring, logging, and service management capabilities.

While it is designed as a drop-in sysvinit replacement and as such makes use of existing SysV init scripts, the systemd package can be installed safely alongside sysvinit and started via the init=/bin/systemd kernel option. The systemd-sysv package provides the /sbin/init replacement.

For more information on this topic, see the Debian wiki.

The legacy secure sockets layer protocol SSLv3 has been disabled in this release. Many system cryptography libraries as well as servers and client applications have been compiled or configured without support for this protocol.

The Linux kernel features a security mechanism which nullifies many symlink attacks. It is enabled in the Debian Linux kernel by default. /tmp-related bugs which are rendered non-exploitable by this mechanism are not treated as security vulnerabilities. If you use a custom Linux kernel you should enable it using a sysctl setting:

echo 1 > /proc/sys/fs/protected_symlinks

In some rare cases the security support for a package shipped in a Debian release needs to be terminated prior to the end of support for the full distribution. Jessie provides a new package (debian-security-support) which emits a warning if support for a package needs to be terminated in advance. It also documents packages where the scope of security support is limited. As such, it is recommended to install debian-security-support on all security-relevant systems.

Continuing on the path set by Wheezy, more packages have been built with hardened compiler flags. Also, the stack protector flag has been switched to stack-protector-strong for extra hardening. Note that the hardened build flags are not enabled by default in gcc, so they are not used automatically when locally building software.

New in this release is the needrestart package. When installed, it will perform a check after each APT upgrade session. If any services running on the system require a restart to take advantage of changes in the upgraded packages then it offers to perform these restarts. It is recommended to install needrestart to ensure that security updates in libraries are propagated to running services.

Along with the older MySQL 5.5, Jessie ships the new MariaDB 10.0. See the Debian MySQL Team wiki page for more information. Only one of them is likely to be included in Debian 9.

Note that upstream support for MySQL 5.5 will cease in December 2018 (and Debian security support will have to follow that), while MariaDB 10.0 will receive upstream security support until March 2019.

The Horde Application Framework is available in Jessie, via the php-horde package.

The Debian Games Team proudly presents the Debian Games Blend consisting of 33 metapackages which simplify the installation of games per category. The selection includes among many others strategy, simulation, card, and programming games. Debian Games also offers developers a quick way to install recommended software for developing games in the C++, Java, Perl, or Python 3 programming languages. Content developers will find useful tools for creating game art in games-content-dev. The project homepage provides screenshots and further information and offers a compact overview about all games including Debian's finest games.

The Debian Med team has again considerably increased not only the number of packages in the fields of biology and medicine but also their quality in terms of testing (at package build time as well as autopkgtest). These enhancements in version 2.0 of the Debian Med Blend metapackages reflect the demand from scientists for reliable software to provide reproducible results. Visit the Debian Med tasks pages to see the full range of biological and medical software in Debian.

Due to the continuous work of the Debian Science team not only new scientific applications were added to the Debian package pool but also new fields of science are covered by certain applications. Visit Debian Science tasks pages to see the full range of scientific software inside Debian.

During the jessie development cycle many changes from UbuntuGIS were merged back into Debian GIS. The collaboration with UbuntuGIS and OSGeo-Live projects was improved, resulting in new packages and contributors. Visit Debian GIS tasks pages to see the full range of GIS software inside Debian and the Debian GIS homepage for more information.

Jessie ships with 799 source packages (442 updated, +130 new ones since Wheezy) which will be maintained by the Java Team. Notable changes: