Chicken Pellets 

The bulk of your chicken feed will likely be commercially-made chicken pellets. This can actually be the most confusing part too. Chicken feed pellets come in various formats, probably offering a lot more choice than a simple backyard chicken flock needs. To get the best eggs, you should try to get pellets marked as "layer pellets". Pellets are your best choice. Chicken feed in a powder form is called "mash", and is more likely to be messy. Stick to pellets.

Whole Grains 

To add some variety and more nutrition, give your chickens an occasional handful of cracked corn or other grains. Toss it into their straw or outside pen, so they can go scratching for it. Mixed grains of this kind for feeding chickens is called "scratch", and should only be a supplement to the pellets. You'll have yourself some fat chickens if you only feed them corn and grains.

Bugs and More Bugs 

Chickens do eat more than just pellets and grain though, which can be pretty handy for your garden or yard. Any bugs that enter their pen will most likely get pecked up and eaten. You should encourage this as often as you can, and even let your birds loose in your yard sometimes. They won't harm your plants, though their scratching might uproot young seedlings. It's free feed for chickens, and will help your garden to be bug-free.

Kitchen Leftovers 

And another place for "free" food is your own kitchen. Chickens will actually eat just about anything organic you would normally throw out (or compost). Vegetable peelings, ends, rinds and skins will all be loved by your chickens. Same goes for fruit, though most chickens won't eat citrus peelings. Cooked beans or pasta could go into the chicken pen as well.

Calcium and Grit 

Two extras that you need to know about when feeding your chickens are calcium and grit. Chickens need calcium so they can produce healthy shells for their eggs, and they need grit to help them break down their food since they don't have teeth. Though tempting, do not feed egg shells back to your chickens for calcium. Chickens are more likely to start pecking at their own eggs if you do this. You can buy ground oyster shell that is a much better idea. As for grit, even birds with a access to outside dirt and rocks should have it added to their feed occasionally. Chicken grit can be purchased at your local feed store.

How to Feed Chickens 

Now that you know what to feed chickens, you need to know the best way to do it. A typical chicken feeder is a large cannister with a shallow pan at the bottom. You fill up the cannister with your chicken feed pellets, and they pour through into the pan for your chickens. They don't tip over easily, and allows you to feed your chickens for several days at a time.