Intent

Lazy loading is a design pattern commonly used to defer initialization of an object until the point at which it is needed. It can contribute to efficiency in the program's operation if properly and appropriately used.

Applicability

Use the Lazy Loading idiom when

eager loading is expensive or the object to be loaded might not be needed at all

Real world examples

JPA annotations @OneToOne, @OneToMany, @ManyToOne, @ManyToMany and fetch = FetchType.LAZY

Credits

J2EE Design Patterns