Help with health

I am currently making my first game in Unity and I've hit a problem. I cant make health and I cant find a tutorial that tells me how to script it and if I dont know how to script i wont be able to repeat it. So what I'm asking is Can someone teach me how to script this or point me towords a FREE tutorial that can. All help will be greatly appreciated. What I have so far is just the var

`var health : float = 100`

http://answers.unity3d.com/questions/328/how-do-i-make-a-progress-bar

same as health bar

http://answers.unity3d.com/questions/4456

http://answers.unity3d.com/questions/7094/another-gui-question-healthbar