A package is the object that implements Integration Services functionality to extract, transform, and load data. You create a package by using the SSIS Designer in SQL Server Data Tools. You can also create a package by running the SQL Server Import and Export Wizard or the Integration Services Connections Project Wizard. For more information, see Creating Packages in SSIS Designer and Creating New Packages by Running a Wizard.
A basic package includes the following elements:
Control flow elements
These required elements perform various functions, provide structure, and control the order in which elements run. The main control flow elements are tasks, containers, and precedence constraints. There must be at least one control flow element in a package.
These optional elements extract data, modify data, and load data into data sources. The main data flow elements are sources, transformations, and destinations. There does not have to be any data flow elements in package.