Ways to Install and uninstall programs in deb format

Ways to Install & Uninstall .deb packages in Ubuntu:

SOFTWARE CENTER

This is the default GUI installer/uninstaller for Ubuntu to search, install and remove applications.

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SYNAPTIC

This was the old way which can still be used by installing the synaptic package. It works similar to Software Center with a few differences like installing multiple packages at the same time and other details..

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APT-GET & APT-CACHE

This are the default terminal ways in Ubuntu to search, install, update and remove applications.

Searching & Installing
Search & Install

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Remove an application

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Remove an application COMPLETELY (Including config files)

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Update Repositories

APTITUDE

This was the old terminal way of searching, installing, updating and removing applications. Can be used by installing the aptitude package.

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Search & Install

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Remove an application

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Remove an application COMPLETELY (Including config files)

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Update Repositories

DPKG

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Installing a package

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Removing a package

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Purging a package

There are other cases like dselect, PackageKit and GDebi. For Kubuntu you have alternatives like Kubuntu's Adept Manager, newer KPackageKit or Muon.

As an alternative to DEB packages you have alien which can installed RPM packages (Not to be confused with Revolutions Per Minute since that would make Fedora really fast ;) )

I am a bit confused about this question. Ubuntu has its software sources, which are trusted, and comes with reliable/tested software. By passing this concept comes with security issue's. We have to teach the "Ubuntu-way", the software sources are the Achilles heel of Ubuntu. Only very experienced users know their way in the world wide(wild) web, outside the off. software sources. (Via Sourceforge, etc.) Some dev's put a nice uninstall how to/in their software readme. (When you are lucky) But sometimes tar.gz's comes with no uninstall readme at all. Lets not make it fancy or "interesting" to install software outside the off. sources. If I didn't understood your input and question Luis Alverdo forgive me.......