Free range is a method of farming husbandry where the animals are permitted to roam freely instead of being contained in any manner. The principle is to allow the animals as much freedom as possible, to live out their instinctual behaviours in a reasonably natural way, regardless of whether or not they are eventually killed for meat.
An advantage of keeping poultry free-range is that they have plenty of opportunity to scratch about looking for food - chickens are omnivorous in nature, and so will happily eat a wide variety of foods. Insects, seeds and greens all contribute to a healthy diet.
Chickens do not deserve to live in a cage. The natural behaviour of chickens is to forage, to scratch, to dust-bath, to interact and to socialise. Free range hens eating bugs, vegetation and weed seeds lay eggs that have quality of taste, good texture and provide the added benefit of less cholesterol and healthy nutrition.
Chickens can live in a variety of surroundings but are essentially forest birds. Even with free-range systems not many hens are happy to forage in a large open field without protection and shelter from predators. They tend to stay close to their housing. Hens like some overhead cover. The ideal environment for hens is scratching outside under a canopy of trees in woodland.
Eggs from free range hens can cost more than eggs from barn hens. However, for not much more in terms of cost, the difference in the lives of hens is immense.
The taste and quality of a free-range egg speaks for itself.