I have just installed Ubuntu 12.04. It is going to take quite some time to get to know this OS. Here's my question. Regarding the downloading applications for Ubuntu --- what file type do I need to get? I am seeing ".RPM" ".TAR" ".TAR.GZ" ".DEB" and ".SH". So which one is best to get? Thanks.

To install a new program, run the command . This will automatically download a package (RPM), check for dependencies, and install the "program-name". Tar is a file archiver, it works with the tree of directories, but without compression. For a compression, used the gzip, xz, bzip2 and more others. They compress an uncompressed tar archive and retrieve files *.tar.gz, *.tar.xz, *.tar.bz2, and so on. Typically, this files contains the source code of a program, and if you don't have a reason for making the program from sources, don't use it. Must have repositories. DEB-packages NOT compatible with Ubuntu. *.sh is a script file for executing by shell, for example, Bourne Against Shell.

I don't have a Ubuntu system handy, but I'd be *mighty* surprised were apt-get to pull in rpm's.

Go have a look at this page for some Windows-friendly advice re software installing.

Hi,
Ubuntu uses .deb packages. If you want to install .deb packages you'll have to use "dpkg" program. The problem is that dpkg doesn't install the dependencies. Rather run 'apt-get update' (will get a list of all packages from the repo's )and then use 'apt-cache search Packagename'. If it is there, you can install it with 'apt-get install packagename'. apt-get sorts out all the dependencies. tar,tar.gz etc is normally if you want to compile from source.Good Luck

you should use the ubuntu package manager as much as you can, this way you'll get updates and only have verified applications installed. The package manager(apt) can be used in different ways. command line using apt-get, aptitude, the synaptic package manager or the ubuntu software center.

If you are using a desktop edition you'll probably want to use the ubuntu software center. If you're working command line you should use either apt-get or aptitude, I'm not really sure what is recommended atm and both work fine.

if you have something that can't be found with these applications it's not in one of the repositories you are using, there are ways of adding a repository, you'll mainly use this if you want a specific set of applications that are maintained by someone else. or you can download the package on the internet, they come in .deb packages as mentioned before.

Once you've downloaded the right .deb package(keep in mind what your architecture is like 32(x86) bits or 64(x64)) and once you've downloaded the .deb you can just double click it and your preferred package manager will start to install the package. If you don't want to use a GUI you can run:
this will install the package in the same way as described before, only this time command line.

Package management is one of the key issues in the whole architecture, it makes managing installed applications easy and provides a way to use a specific branch type of software like stable and testing for example. Next to that there is the benefit of updates for all your software at once that ubuntu checks on itself.

Yes, I was wrong. Just when I wrote my first post in this thread, I thought about something else.

If you need to install new programs in Ubuntu 12.04 you will need to get these programs from the Ubuntus Software Center.
The guys in Canonical (The company behind Ubuntu) intent is to replace Synaptic with their Software Center.

If you want to download files they should be .DEB extension however is recommended install programs from your repository only.

Good luck to you.