In one sentence, describe what the following article is about:

A clicker is a small plastic box with a metal tab in it. When you press it, it makes a clicking sound.  These are available online or in pet stores, and they cost as little as $1. These are commonly used to train dogs and cats.  It's best to use a clicker specifically designed for training. If you don't have one, though, make a distinct clicking noise with your mouth, or you can use a pen that makes a clicking sound. If your cat is deaf, you can use a pen light to achieve the same results. In order for the training to work, you need to give your cat a reward. A common reward is a special treat of some sort (e.g., tuna or deli turkey), and it should be something that can be given instantly to reward behavior. If the treat is food, it should be cut up into pea-sized chunks. Some cats might respond well to affection or a toy. Use a stick-like object, such as a pen or a spoon. This item should be easily recognizable and used only for training. Your cat will eventually follow this object as a target, so you don't want your cat jumping up to the dinner table to follow her training spoon.  You can make a target stick by putting a Ping-Pong ball on the end of a pencil or chopstick.  Don't use the treat as the target. This will teach your cat to do tricks only when there is a treat involved. Eventually you'll want to be able to get your cats to do tricks without treats (though you should still reward with treats sporadically). Set aside about 5 minutes for each training session, and hold these sessions a few times a day. Wait until your cat is active and hungry (it should be at least 20-30 minutes until mealtime). He will be more interested in the treat and will respond better to the training. Start your training in a location that will be quiet and without distractions. If you have other pets around, try putting them outside or in a separate room while you work on training your cat.
Get a clicker. Have some treats on hand. Get a target item. Find a good time to train. Start in a quiet location.