Installing programs in Fedora 15 is fairly easy.
There are two ways to install stuff.
You can use the add/remove programs function (found under Activities/Applications/System tools or you can do it with yum.
I prefer to use yum, why you ask?
Well i choose yum because it gives you more the feeling that you are working on a computer.
Working with yum is easy, you just need to know a few small commands to use it.
These are the most used commands for me (more can be found with Google):
1. yum update
2. yum install "package name"
3. yum remove "package name"