free good?

The free good is a term used in economics to describe a good that is not scarce. A free good is available in as great a quantity as desired with zero opportunity cost to society.

A good that is made available at zero price is not necessarily a free good. For example, a shop might give away its stock in its promotion, but producing these goods would still have required the use of scarce resources, so this would not be a free good in an economic sense.

There are three main types of free goods:

1. Resources that are so abundant in nature that there is enough for everyone to have as much as they want. An example of this is the air that we breathe.

2. Resources that are jointly produced. Here the free good is produced as a by-product of something more valuable. Waste products from factories and homes, such as discarded packaging, are often free goods (see also dumpster diving).

3. Ideas and works that are reproducible at zero cost, or almost zero cost. For example, if someone invents a new device, many people could copy this invention, with no danger of this "resource" running out. Other examples include computer programs and web pages.

Although it is free to get the MTR ticket (under the basis of BUY 1 GET 1), the service on the passenger transportation are included different costs, e.g. staff cost, operating cost, maintenance cost on facilities and equipment and so on. These resources are limited in nature and are consumed during providing the passenger transportation service. Therefore, the free ticket is not a "free good" in an economic world.

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If a passenger uses the same Octopus card to travel MTR for more then 10 times a week, they may get a discount offer. For example, during 16-22Oct 06, they may get a “Buy One Get One Free” coupon on all pastas in Pizza Hut. Is the fee pasta a free good in economics?

A free good one in which the supply is so abundant that it can satisfy all human wants for them. No one is willing to incur a cost for free goods. Although the free pasta is free of charge, we have to use limited resource to produce that good. Thus, it is not a “free good” in economics.