Ducks are very special, cute and interesting birds. This one is a mallard drake, which is the word for a male mallard. A female mallard is called a hen. You can tell them apart because of their plumage.
As you can see, their feathers are totally different, so it is easy to tell their sex apart. Mallards are the most common kind of duck. Even thogh they are omnivorous, they cannot digest all kinds of food. When people feed ducks, many give them improper food, such as bread. That can make them sick. You should give them natural foods like seeds, peas, insects or even small fish. Ducks have a varied diet, so you have many options.