I have a deb package for installation.Shall I install by dpkg -i my.deb, or by apt?Will both handle the software dependency problem well?If by apt, how can I install from the deb by apt?
How to install a deb file, by dpkg -i or by apt?
software installation;apt;dpkg;deb
When you use apt to install a package, internally it uses dpkg. When you install a package using apt, it first creates a list of all the dependencies and downloads it from the repository.Once the download is finished it calls dpkg to install all those files, satisfying all the dependencies.So if you have a .deb file:You can install it using sudo dpkg -i /path/to/deb/file followed by sudo apt-get install -f. You can install it using sudo apt install ./name.deb (or /path/to/package/name.deb). With old apt-get versions you must first move your deb file to /var/cache/apt/archives/ directory. For both, after executing this command, it will automatically download its dependencies.Install gdebi and open your .deb file using it (Right-click -> Open with). It will install your .deb package with all its dependencies.(Note: APT maintains the package index which is a database of available packages available in repo defined in /etc/apt/sources.list file and in the /etc/apt/sources.list.d directory. All these  methods will fail to satisfy the  software dependency if the dependencies required by the deb is not present in the package index.)Why to use sudo apt-get install -f after sudo dpkg -i /path/to/deb/file (mentioned in first method).From man apt-get -f, --fix-broken           Fix; attempt to correct a system with broken dependencies in place.When dpkg install a package and package dependency is not satisfied, it leaves the package in unconfigured state and that package is considered as broken. sudo apt-get install -f command tries to fix this broken package by installing the missing dependency. 