There used to be a popular tutorial for beginners about this titled How to install ANYTHING in Ubuntu!, however it has not been updated since 2006 and it is a bit outdated (some of it still applies though).
This is a guide containing the most popular and useful ways of using the APT and DPKG commands, and it applies to both Ubuntu and Debian (and their derivatives). I mentioned where super user privileges are required, the ones without a mention can be executed as normal user.
Miro is a great application for watching videos and high-definition TV podcasts in Linux. The latest release is 2.5.1, a bug fix release for the 2.5 series, which has a faster start-up time, a new, revamped library interface, new keyboard shortcuts, a refined interface and lots of bug fixes.
Several months ago I created an article with 5 APT (Advanced Packaging Tool) tips for both Debian and Ubuntu available here. APT is the package manager in Debian and Debian-based distributions, like Ubuntu. Here's part two of that article, with 5 more tips and tricks for APT.
Install the dependencies of an application
Sometimes you need to compile from source a newer version of an application which is already included in the repositories. For example, to install the development libraries for BasKet, you would run as root:
apt-get build-dep basket
addrepo is a simple command line interface for easily adding APT repositories to your sources.list.