Ubuntu – Where to find a detailed catalog of installed packages

In my 12.04 installation I've just discovered a whole lot of nice packages that I knew nothing about (or had forgotten).
So – is there a facility that makes a catalog of all expressly installed packages, complete with a description of each package?
I couldnt find any such facility. So I had to do all the grunt work myself **.

Richard H

**What I did:

• First, «$ aptitude search '~i!~M'» made a list of expressly installed packages. Thank You for this to How to list all installed packages

• Then a Perl script did «$ apt-cache show (name of package)» to "search and generate interesting output from the package metadata" for each package.

• A second Perl script added information from all the README files in /usr/share/doc/

• And third Perl script used Asciidoctor to format the results as an html file, A for accountsservice to Z for Zenity, complete with individual descriptions and links for each package.

My experience suggests that it would be nice if Ubuntu had a single facility that did all this, so as to offer all users such a catalog by default.