The shader used by the material.

	// Toggle between Diffuse and Transparent/Diffuse shaders
	// when space key is pressed
	var shader1 : Shader = Shader.Find("Diffuse");
	var shader2 : Shader = Shader.Find("Transparent/Diffuse");
	function Update() {
		if (Input.GetButtonDown("Jump")) {
			if( renderer.material.shader == shader1 )
				renderer.material.shader = shader2;
			else
				renderer.material.shader = shader1;
		}
	}

using UnityEngine;
using System.Collections;

public class Example : MonoBehaviour {
    public Shader shader1 = Shader.Find("Diffuse");
    public Shader shader2 = Shader.Find("Transparent/Diffuse");
    void Update() {
        if (Input.GetButtonDown("Jump"))
            if (renderer.material.shader == shader1)
                renderer.material.shader = shader2;
            else
                renderer.material.shader = shader1;
        
    }
}

import UnityEngine
import System.Collections

public class Example(MonoBehaviour):

	public shader1 as Shader = Shader.Find('Diffuse')

	public shader2 as Shader = Shader.Find('Transparent/Diffuse')

	def Update() as void:
		if Input.GetButtonDown('Jump'):
			if renderer.material.shader == shader1:
				renderer.material.shader = shader2
			else:
				renderer.material.shader = shader1