Closed-loop systems are able to correct in order to meet target results. Normally a sensor is used to look at the output and adjust the process accordingly. This is called feedback.
A file with an extension of .DAT is known as a Data (General). These .DAT files can be opened on Windows and Apple using programs ...
A .dat file is often a file from a popular application that got its extension changed by Outlook, the computer or the copier that saved the file. When receiving a .dat file, try to think what kind of file it could be: a Word doc, an Excel file, a Powerpoint file, an Adobe .pdf or a scanned jpg? According to your estimation, try to change the extension to the expected extension and see if you can open it.