If you do not run this command, you could be getting older versions of various packages you are installing, or worse, dependency issues.If you have just added a PPA and have not updated, nothing from the PPA will work at all as you do not have a package list from that PPA or repository.In a nutshell: It is It updates the available software list on your computer.
But the available software and versions might change, so a "update" will hit the server and see what software is available in order to update its local lists (or catalogs). This is the step that actually retrieves information about what packages can be installed, including what updates to currently installed packages packages are available, from Internet sources.
When you install packages with a GUI interface (the Update Manager, the Software Center, or the Synaptic Package Manager), the work of than by the automatic check performed by running the Software Updater / Update Manager? And are you able to you make it happen again, or has it happened just the one time? (Btw, is this intended as a separate answer, or should it be converted to a comment?
If it's an isolated anomaly, I wonder if maybe the problem is due to a temporary server misconfiguration.
ah sounds like it's just a convention thing then.
So I'm assuming it's really no that necessary especially if you are just using basic packages with basic commands that don't get updated usually.
Problem in my situation is that is an option for the apt-get program to use which updates the package lists from a server on the internet.The package lists provide the apt-get utility with important information about the software packages that you can install using apt-get.apt-get uses these lists to determine which software to install when given a command to install.For example would install the Guake terminal as it is currently listed in my computer's local software lists.This may not, however, be the appropriate version, or if the program is new, it might not be available at all.Thus, when installing software with apt-get, you typically type simply makes sure your list of packages from all repositories and PPA's is up to date.