apt-get install {package} Install the new package. If package is installed then try to upgrade to latest version apt-get install zip/apt-get install lsof samba mysql-client
apt-get remove {package} Remove/Delete an installed package except configuration files apt-get remove zip
apt-get –purge remove {package} Remove/Delete everything including configuration files apt-get –purge remove mysql-server
apt-get update/apt-get upgrade Resynchronize the package index files and Upgrade the Debian Linux system including security update (Internet access required)
apt-get update/apt-get dist-upgrade Usually use to upgrade to Debian distribution. For example Woody to Sarge upgrade. ‘dist-upgrade’ in addition to performing the function of upgrade, also intelligently handles changing dependencies with new versions of packages; apt-get has a “smart” conflict resolution system, and it will attempt to upgrade the most important packages at the expense of less important ones if necessary.