A convenience is a luxury that is intended to save a consumer time or frustration. A convenience store at a petrol station, for example, sells items that have nothing to do with gasoline/petrol, but it saves the consumer from having to go to a grocery store. "Convenience" is a very relative term and its meaning tends to change over time.
convenience method is an operation on an object that could be accomplished by a program consisting of more basic operations on the object. Convenience methods are usually provided to make the API easier and simpler to use or to allow specific programs to create more optimized implementations for common operations. A similar definition holds for a convenience property.