A package is a block that can contain only declarations, default statements, and procedure blocks. The package forms a name scope that is shared by all declarations and procedures contained in the package, unless the names are declared again. Some or all of the level-1 procedures can be exported and made known outside of the package as external procedures. A package can contain zero or more procedures, and any or all procedures in a package can be exported. Use a package to implement multiple entry point applications.