Structures
The term "structure" refers to data that's built up from other types. Because arrays are a special case, they are treated separately in Chapter 12. This section deals with user-created structured data—structs in C and C++ and Structures in Microsoft Visual Basic. In Java and C++, classes also sometimes perform as structures (when the class consists entirely of public data members with no public routines).
You'll generally want to create classes rather than structures so that you can take advantage of the privacy and functionality offered by classes in addition to the public data supported by structures. But sometimes directly manipulating blocks of data can be useful, so here are some reasons for using structures: