What is a free video editing program I could download?

Me and my friend have a youtube channel, and of course we make videos. We make them on my Ipod Touch(the new one I am not sure which generation that is, it has the camera on the front and back and it is 32g...I think it is the 4G but im not sure.) and we would like to edit them but I don't have an editing program on our computer. So what is a free video editing program I could use? I would like it to be easy to use but still have some cool effects..Thank you! <3