I know that on a local non-networked machine, it's possible to use the local apt database to search for packages to install using apt-cache search and apt-cache show. These commands print a package's short description summary, but not the package's extended description.I know also that once a package's *.deb file has been downloaded onto a local machine it's possible to get that package's very useful extended description using dpkg --info /path/to/foo.deb, which reads the contents of a deb package's /info or /Debian/control file. This extended description is also available on-line, and is the text we all see when viewing a package on http://packages.debian.orgHow can I get a local copy of all packages' extended descriptions so that I can better decide which packages to download?As a follow-up, in response to @Gilles request for an example:# apt-cache search ^apt$apt - commandline package manager# apt-cache show apt | sed -n '/^Desc/,/^Desc/p'Description: commandline package managerDescription-md5: 9fb97a88cb7383934ef963352b53b4a7Description: commandline package managerDescription-md5: 9fb97a88cb7383934ef963352b53b4a7#dpkg --info /var/cache/apt/archives/apt_1.4_amd64.deb | sed -n '/^ Description/,${p}' Description: commandline package manager  This package provides commandline tools for searching and  managing as well as querying information about packages  as a low-level access to all features of the libapt-pkg library.  .  These include:   * apt-get for retrieval of packages and information about them     from authenticated sources and for installation, upgrade and     removal of packages together with their dependencies   * apt-cache for querying available information about installed     as well as installable packages   * apt-cdrom to use removable media as a source for packages   * apt-config as an interface to the configuration settings   * apt-key as an interface to manage authentication keys
Getting a local copy of Debian's extended package descriptions
debian;apt;dpkg