APT essentials

With this commands most of your problems with linux packages can be solved.

apt-get update          /* update list of available packages
apt-get dist-upgrade    /* upgrade your linux distro
apt-cache search        /* search <name> packages
apt-cache show <name>   /* display package information for package
apt-get install <name>  /* install package <name>
dpkg -L <name>          /* list files installed for package <name>
dpkg -l                 /* list all installed packages
apt-get remove <name>   /* remove package <name>
apt-get remove --purge  /* remove also configuration files <name>
apt-get autoclean       /* /var/cache/apt/archives delete old archives
apt-get clean           /* delete apt archive

/var/lib/dpkg/status    /* text file which holds status of packages
                        /* can be edited to solve problems with      
                        /* broken packages