Unity crashes when i play my scene.

using UnityEngine;
using System.Collections;

public class PlayerCharacteristics : MonoBehaviour 
{
	public float playerHealth = 100.0f;

	void Start()
	{
		playerHealth = 100.0f;
	}

	void Update()
	{
		playerHealth -= 1;

		while (playerHealth == 0.0f) {
			playerHealth = 0.0f;
		}

	}
}

This is the only code in the project that i have written myself. Unity just crashes when i press play.

Check the Editor Log.

Looks like you have a while loop which doesnt end. Once inside the loop it cant break out. Avoid usage of while if you can. On top of that, the loop doesnt actually do anything except kill your program.