Public goods

• Public goods are Non-excludable (It is difficult or costly to prevent individuals from benefiting from the good, regardless of whether they pay for it), and Non-rivalry, (Consumption by one individual does not reduce the availability of the good for others; it is "non-depletable")
• Private goods are excludable (Producers or sellers can prevent individuals from consuming the good if they do not pay for it) and rivalry (Consumption by one individual reduces the availability of the good for others)