A structure is a way of organizing multiple variables, often of different types, into a group. For example, the characteristics of several devices, such as motors, can be described using the same data groups.

Take an electric motor, for instance. Such a motor can have many technical parameters, but for simplicity, let's narrow down the range of these parameters.

In this case, the motor has a text identifier, typically a KKS identifier in larger installations. Then there are voltage and current measurements, an operating mode, and a status indication. These data belong together and describe a motor. In the example above, this motor is, for example, the first motor of a hydraulic block. In the case of multiple motors, this structure remains—only the parameters change, as this makes it easy to handle the data uniformly:

This is what it looks like in the TIA Portal when the structures are open:

The display of structures can be limited to just their names, with an arrow placed in front of the name to close the content: