A pellet hopper is what you put your pellets in. The grill will automatically help itself from the hopper and use it to maintain the temperature you want it to. More heat requirement will use more pellet, and less heat will use less. What you need to make sure is that you have a good sized pellet hopper so that your grill can keep using from it and you do not have to keep refilling the hopper too often. There are pellet grills out there that are powerful and gentle enough to be cooking for hours, and sometimes overnight, all thanks to its large pellet hoppers that keep replenishing and refueling the fire all throughout.
Pellet grills have a couple of very distinct advantages and disadvantages. The best can hold a constant temperature more or less indefinitely, provide even smoke at low temps, cook w/o smoke at high temps, make it possible to evenly cook several different meats and do a good job at two zone cooking. The Yoder excels at these. It is built like a tank, easy to use and I love it. One drawback for some pellet grills is the inability to reach high temps and sear. With the GrillGrates I have reached almost 600F and can sear with the best of them. Drawbacks. Well, it is a bit tricky to clean, but I guess I am keeping it cleaner than I did my previous grills!
Pellet grills come in many different sizes that accommodate food as per those sizes. However, even the smaller kinds are able to cook up a meal for a large family of 4 to 5 at a time! The larger ones are obviously able to accommodate large portions of meat and other food in it. In fact, some large pellet grills are used to cook up a whole baby lamb or large fishes at a time! This is one appliance that has been proven ideal for feeding a lot of heads at a time without the stress and the hard work of course, making it great for small to medium parties and get-together.
Another option is to put a griddle (or GrillGrates) on the pellet smoker when it's cranked to high heat, get it blistering-hot, add just a little oil to prevent sticking, and sear by conduction on the metal. It should take only two to three minutes per side. This is a good technique for reverse-seared meats: You start them indirect, low and slow on the cooking grate, with a little smoke, and then sear the surface with direct contact to the hot metal griddle to create a delicious brown crust. It's not as good as searing directly over hot coals or gas, but it's a good compromise.

So that brings me to the one thing I have learned in all this that I basically read when I was getting started. One of the biggest keys is “Temperature Control”! If you want consistent food make sure you get that under control. It is the key to solid consistent food! Once you get your food consistent you can experiment with a lot of other things. But if you can’t get that down, you will always be looking for another magic bullet. The number one magic is temperature!
One comment I see a lot in various forums like PelletHeads.com is that you want as much efficiency as you can get. As with lump charcoal, this means burning as clean of a cook as you can with as little ash as possible. Different pellet mixes will produce differences in what you get in this area, and the cooker you’re using will dictate this to some degree as well.
If you live in an area where wood furnaces are used (not like down here in FL where a few heat strips will do the trick), you may also be familiar with pellet furnaces. In short, pellets compressed from sawdust and wood shavings fill a hopper and are then fed into a burn pot using an electric auger system. The auger, which is basically a long screw, delivers pellets to the burn pot based on the speed dictated by the unit’s thermostat. As the burn pot ignites, the pellets burn. Heat then carries through the home via convection (air driven) means, thus allowing air flow and a blend of warm and cool air to maintain steady, even burn temperatures. A heat exchanger separates the smoke fumes from the warm air, thereby warming the room without smoking everyone out.

This piece of junk did not work when I received it fresh out of the box & now it's broke again!!! What a waste of money! First issue was a temp control module board, which the manufacturer actually sent me directly & I had to install it. Now after about 6 months of using it approximately 12-14 times, it won't even power up. I don't even want to attempt to fix it again!! I am going to spend the extra money & buy a Traeger!!
Pellet Hopper – One of the reasons we all buy a pellet smoker for is the long cooking time. It’s an automated grill, but it needs to be provided with the right amount of pellets in the hopper. Those grills are used for long, often all night long meat smoking. That’s why it’s important for the pellet container to be very big. Here you get a 40 pound hopper capacity. You can be sure you won’t run out of fuel during longer cooking.