Chicken Behavior

The term chicken refers to both male and female birds. Cockerels are the males also known as cocks and roosters. Hens are the females (the ones who lay the eggs). Hens under 1 year of age are called pullets.
Fallacy: You need to have a rooster for your hens to produce eggs. Wrong. The eggs are still produced it just means that, without a rooster to fertilize them, there is no chance of them turning into chicks.
Sexing chickens. For most chick breeds, it's nearly impossible to tell male and female apart, so unless the guy in the feed store bought only females (and even then there's a 5% chance it might be male) it's pot luck. You can't tell until they are many weeks old and start to display certain behaviors, and even then its not certain. We had a hen who nearly went in the pot because she displayed such aggressive behavior as a youngster. We were convinced she was a rooster...we were wrong. If you buy your chicks from the average backyard breeder rather than a large hatchery it is unlikely they will have the skills to sex the chick even on the first day.
Buying "straight run" versus "sexed": Because many people cannot keep roosters or because they want their chickens primarily for eggs, many hatcheries sell either sexed or straight run chicks. Straight run means you get the chicks as they come, randomly male or female. Sexed means you're buying all females or all males.
Broody hen. A hen who insists on sitting on the eggs attempting to hatch them.

Here's more about eggs:

Different chickens lay different colored eggs naturally.
Store bought eggs will not hatch (unless specifically marked fertile).
Eggs can be frozen, just take them out of their shells and freeze them in a plastic bag. You can also separate and freeze just the whites, great to whip into omelets or make meringues.
Very fresh eggs are hard to peel when hard-boiled. Once they are several days old the air sac will expand and the shell will come off much more easily--not usually a problem with store bought eggs!
Try not to wash eggs. They have a natural antiseptic membrane that helps keep out infection. If they are dirty just wipe them with a dry cloth.