Chicken soup is a prototypical comfort food. For many people it's good example of home cooked food. The smell of chicken soup evokes a sense of home and being nurtured.
The basic ingredient is chicken broth. The broth can be bought or made.
Other common ingredients are pieces of chicken, vegetables (carrots, potatoes, celery, mushrooms, onion, corn), and carbohydrates in the form of pasta, matzo balls or dumplings. Then there are the spices: salt, pepper, bay leaves, ginger.