+life. A few aliases (like those involving //grep// or //ls//) use the option
+//--color=auto// for colourizing output. That option is part of **GNU**
+implementations of these tools, and will only be used if such an implementation
+is detected.
+
+: **acp** (//apt-cache policy//)
+With no arguments prints out the priorities of each source. If a package name
+is given, it displays detailed information about the priority selection of the
+package.
+
+: **acs** (//apt-cache search//)
+Searches debian package lists for the regular expression provided as argument.
+The search includes package names and descriptions. Prints out name and short
+description of matching packages.
+
+: **acsh** (//apt-cache show//)
+Shows the package records for the packages provided as arguments.
+
+: **adg** (//apt-get dist-upgrade//)
+Performs an upgrade of all installed packages. Also tries to automatically
+handle changing dependencies with new versions of packages. As this may change
+the install status of (or even remove) installed packages, it is potentially
+dangerous to use dist-upgrade; invoked by sudo, if necessary.
+
+: **ag** (//apt-get upgrade//)
+Downloads and installs the newest versions of all packages currently installed
+on the system. Under no circumstances are currently installed packages removed,
+or packages not already installed retrieved and installed. New versions of
+currently installed packages that cannot be upgraded without changing the install
+status of another package will be left at their current version. An update must
+be performed first (see au below); run by sudo, if necessary.
+
+: **agi** (//apt-get install//)
+Downloads and installs or upgrades the packages given on the command line.
+If a hyphen is appended to the package name, the identified package will be
+removed if it is installed. Similarly a plus sign can be used to designate a
+package to install. This may be useful to override decisions made by apt-get's
+conflict resolution system.
+A specific version of a package can be selected for installation by following
+the package name with an equals and the version of the package to select. This
+will cause that version to be located and selected for install. Alternatively a
+specific distribution can be selected by following the package name with a slash
+and the version of the distribution or the Archive name (stable, testing, unstable).
+Gets invoked by sudo, if user id is not 0.
+
+: **ati** (//aptitude install//)
+Aptitude is a terminal-based package manager with a command line mode similar to
+apt-get (see agi above); invoked by sudo, if necessary.
+
+: **au** (//apt-get update//)
+Resynchronizes the package index files from their sources. The indexes of
+available packages are fetched from the location(s) specified in
+/etc/apt/sources.list. An update should always be performed before an
+upgrade or dist-upgrade; run by sudo, if necessary.