.deb (Debian Package) files are primarily found in the distro's repository. You generally should not deal with them directly, but rather through your package manager, such as apt, Synaptic, or Adept. You can also browse the repository online to download individual .deb files individually.
Go to the following link and your answer is there: http://www.file-extensions.org/deb-file-extension
RPM packages are installation packages designed for Red Hat based system. They are similar to .exe files for Windows, and .deb files for debian systems.
Open up Firefox, go to the Skype official website, click get skype, click download for Linux then click the first Ubuntu download. Open the file and install it as a normal .deb package.
The Linux operating system command gunzip does many things. The main thing that gunzip does it compress files so that they are smaller and easier to upload and download.
There are a variety of different Linux software downloads available for download. One can download basic Linux for free from sites such as Download Linux Free and Softonic.
These are different file types used under Linux 1. .tar and archieve files and need to be untared before use 2. .bin could be binary files in(elf format) 3. source file could be normal ASCII files.
OK first thing you should know is that I have horrid grammar skills. Second it depends of the game files. If your game files are .exe you will need to install and run wine. If your games are .deb just double click on the files. If .tar.gz right click on the files and choose extract, then there will be a new folder in the directory your .tar.gz was with the same name. Go into that folder using the terminal and type "./install" lastly you may need to change the permissions but that is another google search.
You can download Linux Mint here: www.linuxmint.com/download.php
I assume you are talking about packages in Linux which can be packaged in many different ways. Just for clarification the packages we are talking about here are like .exe files in windows they are packages that install programs. You cannot use .exe in Linux because these files are made for Windows system. Linux distributions have something called a package manager which handles all of the packages (or programs) installed. All Debian based distros (Ubuntu, Linux Mint, Debian,) use .deb files for programs. All Red Hat based distros (Opensuse, Red Hat, Fedora) use .rpm files for programs. All linux distros have one thing in common. You do not need to use firefox to download programs you can use Software Manager/Synaptic/Software Center to install programs on your system. This works because the system uses repositories. These are websites where all of the programs come from. You should search these repositories you might find the program you are looking for. Also if you do not know what Linux distribution to try I would try Linux Mint. It is very user friendly
do your own research
There is no version of iChat for Linux.
There is no version of StarUML for Linux.