In all the documentation and posts I've read for the RasPi the recommended way to upgrade a distribution and its packages is to use sudo apt-get update followed by sudo apt-get upgrade. But elsewhere it's recommended that you use sudo apt-get dist-upgrade rather than sudo apt-get upgrade. Microelectronics Jacob Milliman Graebel Van Lines. See, for example,:- 'The upgrade option only installs new version of the packages that are already installed on the system (and yes, kernel updates belong to them). However, sometimes the updates change dependencies: for example, a new version of a package will no longer depend on a library that you have installed, or will require installation of additional libraries. The upgrade option will never remove installed packages that you no longer actually need. However, the dist-upgrade option can 'intelligently' handle changes in the dependencies system. This includes removing packages that are no longer necessary or resolve conflicts between packages that arose because of changes in the dependencies.'