Fields are repositories of data that hold constant or variable values. These values consist of all data types, including characters, numbers, dates, times, integers, strings, and so on. The fields serve as representatives or aliases of those values. Everywhere you insert a field essentially places the actual value or variable into that location. Since fields can contain any data type, they play a pivotal role throughout the application, allowing you to implement internal or external system values in order to institute processes, perform tasks, and execute processes.
Process Designer enables you to create, assign, and implement fields, so they can be passed to data controllers and used in the proper context to provide the intended value when and where it is needed. When working with external systems, fields work hand-in-hand with event listeners to get the data to where it is needed. Several fields are dependent on field mappings to obtain the values and the process will not run without them, such as external system ID, requester, proposed date, and so on. See also "Inserting fields".