packages for (k)ubuntu

[roberto]

hello, i am an old linux user but i am going to know more about ubuntu
and derivatives

that's why i need to know the following:
"each" of the packages available for ubuntu is also available for kubuntu ?
or is there any package which comes out for the first and later for the second ?

i ask this question since i see that the package list for ubuntu is
very updated but i'd like to use kubuntu instead

thank you
-- 
roberto