For what is LSB-core, LSB-base, lsb-release and so on?

Hi!

For what are these LSB-packages good?

lsb-base (installed)
lsb-release (installed)

Do I need lsb-core package? (not installed)

Which LSB-packages must I have for default?

Did :

lsb_release -si = Ubuntu
lsb_release = No LSB modules are available.

What are LSB modules? Are they important?

LSB is Linux Standard Base. You can read about them on special web-site https://wiki.linuxfoundation.org/lsb/start .

The packages from your list really came from one same source - lsb package.

Standards (especially open source and free standards) are almost always good.
Some software on installed system may require special LSB modules.
It seems that your system does not need lsb-core , so this package is not installed.
But there package which require lsb-core - you can get their list by running apt-cache rdepends lsb-core on your system. So the exact list of LSB modules installed depends on installed software, so this is about dependencies.

ok, thanks for the info.