when I enter

$ apt-cache showpkg gnome-devel

in my terminal, I get :

Package: gnome-devel

Versions: 

1:3.0+6ubuntu4 (/var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_quantal_universe_binary-amd64_Packages)

Description Language: 

    File: /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_quantal_universe_binary-amd64_Packages

MD5: 4682dc9d7825daf220363435b46d793b

 Description Language: en

File:               /var/lib/apt/lists/fr.archive.ubuntu.com_ubuntu_dists_quantal_universe_i18n_Translation-en

                  MD5: 4682dc9d7825daf220363435b46d793b





Reverse Depends: 

Dependencies: 

1:3.0+6ubuntu4 - anjuta (2 2:3.0) anjuta-extras (2 3.0) devhelp (2 3.0) glade (2 3.10) gnome-devel-docs (2 3.0) gnome-platform-devel (0 (null)) 

Provides: 

1:3.0+6ubuntu4 - 

Reverse Provides:

But there are some details that I don't understand.

• What does "1:3.0+6ubuntu4" mean here? Is it the minimum Ubuntu version for this package ?


• What does (0 (null)) mean for the dependency package gnome-platform-devel? I think it means this package is just recommended : am I right ?


• In ajunta (2 2:3.0) : what does the leading "2" in version number (2 2:3.0) mean? I think that it is for ">=" : am I right ?