$ curl cheat.sh/
 cheat.sheets:apt-get 
# apt-get
# Command-line interface to APT package management

# Update the local database of available packages, as discovered from package
# index file found in their sources. This does not actually update your
# installed software! For that, keeping reading.
apt-get update

# Upgrade installed packages, but there may be exceptions, such as important
# kernel packages. Also, packages will not be removed, like if they're
# deprecated, with this method.
apt-get upgrade

# Unlike the above, this will upgrade all of the installed packages, and
# perform other actions required for a successful and thorough upgrade. This
# will also allow for upgrading to the next minor release of your
# distributions, such as from Ubuntu '16.04.1' to '16.04.2'.
apt-get dist-upgrade

# Clean out (completely) the follow locations of saved DEB files:
#
#   /var/cache/apt/archives/* /var/cache/apt/archives/partial/
#   /var/lib/apt/lists/partial/
#   /var/cache/apt/pkgcache.bin /var/cache/apt/srcpkgcache.bin
#
# This will also, thanks to the provided flag, be somewhat verbose.
apt-get clean -s

# View the changelog for the firefox package. Useful prior to or after upgrade.
apt-get changelog firefox

# Download PKG (one or more) without actually installing or extracting them. A
# good use for this might be to upgrade an offline system, by downloading the
# packages on a system using an Internet-able machine. Files are downloaded
# into the CWD.
apt-get download PKG

# Install PKG (one or more), bringing in dependencies and, provided settings
# allow it, install recommended and/or suggested packages.
apt-get install PKG

# At times, dependencies won't be installed, yet you still need them; the
# following command will often fix this, and is usually suggested to the user.
apt-get -f install

# Remove PKG, while also purging system-wide configuration files for it.
apt-get purge PKG
# Alternative syntax to the above.
apt-get remove --purge PKG

# Often used to first update the local database of packages, then, only if
# successful, a full system upgrade is started.
apt-get update && apt-get dist-upgrade

# Download specified package (firefox, in this example) and all packages marked
# thereby as important or dependencies. Files are downloaded into the CWD.
apt-get download firefox `apt-cache --important depends firefox |
    awk '{if(NR>1){printf("%s ", $2)}}'`

 cheat:apt-get 
---
tags: [ packaging ]
---
# To fetch package list:
apt-get update

# To download and install package updates:
apt-get upgrade

# To download and install the updates AND install new necessary packages
# AND remove any packages that stand in the way of the upgrade:
apt-get dist-upgrade

# Full command:
apt-get update && apt-get dist-upgrade

# To install a new package(s):
apt-get install <package>...

# To download a package without installing it. (The package will be downloaded in your current working dir)
apt-get download <package>

# To change cache dir and archive dir (where .deb are stored):
apt-get -o Dir::Cache="/path/to/destination/dir/" -o Dir::Cache::archives="./" install ...

# To show apt-get installed packages:
grep 'install ' /var/log/dpkg.log

# To silently keep old configuration during batch updates:
apt-get update -o DPkg::Options::='--force-confold' ...

 tldr:apt-get 
# apt-get
# Debian and Ubuntu package management utility.
# Search for packages using `apt-cache`.
# More information: <https://manpages.debian.org/latest/apt/apt-get.8.html>.

# Update the list of available packages and versions (it's recommended to run this before other `apt-get` commands):
apt-get update

# Install a package, or update it to the latest available version:
apt-get install package

# Remove a package:
apt-get remove package

# Remove a package and its configuration files:
apt-get purge package

# Upgrade all installed packages to their newest available versions:
apt-get upgrade

# Clean the local repository - removing package files (`.deb`) from interrupted downloads that can no longer be downloaded:
apt-get autoclean

# Remove all packages that are no longer needed:
apt-get autoremove

# Upgrade installed packages (like `upgrade`), but remove obsolete packages and install additional packages to meet new dependencies:
apt-get dist-upgrade

$
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