Behaviour.enabled

Description

Enabled Behaviours are Updated, disabled Behaviours are not.

This is shown as the small checkbox in the inspector of the behaviour.

#pragma strict
// Required when Using UI elements.
public class Example {
	public var pauseMenu;
	public function Start() {
		//Enables the pause menu UI.
		pauseMenu.enabled = true;
	}
}

using UnityEngine;
using System.Collections;
using UnityEngine.UI; // Required when Using UI elements.

public class Example : MonoBehaviour 
{
	public Image pauseMenu;
	
	public void Start()
	{
		//Enables the pause menu UI.
		pauseMenu.enabled = true;
	}
}