What is jailbreaking you ask? Well you in the right place.
Jailbreaking is taking your iDevice and adding another app store like application. This app (Cydia in most cases) is an app store which allows you to get other apps that apple doesn't approve of for their app store.
One of the main reasons people jailbreak their iDevice is to get themes for your iDevice. You may have seen these themes on different peoples iDevice in YouTube video's and they jailbreak there devce in order to get access to the themes.
If you discovered this website from a advertisement in Graal, then with Cydia you can get iFile, which you can find shield and sword codes with, and hack the game, but let's not go there in this post.
In cydia you can do many things
Browse the store for new apps
Search for apps
Look for the most popular apps
Add sources to get more apps
And check to see which programs are available to jailbreak your iDevice
With adding sources, you must know the repositories web address. You then will download the package and have access to new applications. Many repo's have cracked apps, or apps you would have to pay for through cydia but now get for free.
So, have you not known what jailbreakmg was before reading this guide, I sure hope it helped and got you to decide whether or not jailbreaking is right for you.