dpkg is the software at the base of the package management system in the free operating system Debian and its numerous derivatives. dpkg is used to install, remove, and provide information about .deb packages. dpkg itself is a low level tool; higher level tools, such as APT, are used to fetch packages from remote locations or deal with complex package relations. Tools like aptitude or synaptic are more commonly used than dpkg on its own, as they have a more sophisticated way of dealing with package relationships and a friendlier interface.