Processes commonly need to read properties that other processes write. Maps contain points, which work like variables that store only the latest value written to them. In other words, point value maps are repositories of information that any process can read and write at run time.

In the example of reading the current operating state of a machine, processes do not require knowledge of every change in operating state that occurs, but rather, only the current state. Point value maps are designed for this use case, where the device software must store a value in memory that readers and writers can access with no flow control.

Map Format:
Maps and map points persist until the device code restarts. In other words, maps and points created before a restart no longer exist in memory after the restart.
Map points consist of a key-value pair.
Each map can contain multiple points, which are identified by name.
Multiple maps can exist simultaneously, each of which is identified by name.
Points support values whose data type is string, double, integer, Boolean, or variant.
Points support a few types of attributes: a property that indicates whether the point value is valid, a timestamp that indicates when the value was written, and generic user-defined attributes.