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What is a peanut

peanuts are pulse, not nuts. Like beans. A peanut also is a software component written in php.
Peanuts are instances of direct or indirect subclasses of PntObject. Peanuts have properties, whose values you can get and set.

What makes a peanut a component is the availability of meta data. A lot of what the phpPeanuts framework does by default is based on this meta data. For example, you do not have to write getter and setter methods for all your properties, becuase the framework will produce default behavior if there is no getter/setter method for a property.