What is the IT department of an enterprise?

The IT department of some enterprises mainly maintains the company's website, local area network and system, and is responsible for data maintenance if there is PDM or ERP. Personally, if an enterprise has ERP or PDM, there should be several people to maintain the data. Miscellaneous data or erroneous data caused by software problems or misoperation should be cleaned up or repaired in time to avoid affecting the correctness of system decision. Everyone knows that the most important thing in informatization is the correctness of basic data. But I'm afraid there are not many that can really guarantee the correctness of the data. Of course, maintaining data is not a profound thing, so its position in the enterprise is not necessarily high, but its role is really huge.