Product data management (PDM) is the process behind automatically managing all the design data contained in engineering shop drawings.
Back in the day, It was the collective bills of material on a set of shop drawings that were the primary source of all the procurement information. That Bill of material often got turned into spreadsheets so that the data could be entered into a companies purchasing system. The parts and assemblies were numbered and the data entered into the companies production information system
One of the drawbacks to this, is that a lot of information was not always captured by the bill of material. The paint colour, the material finish, special instructions for fasteners were often contained only in notes on the drawing and this information had to be tediously copied one at a time into a companies production information system.
Sometimes there were no actual shop drawings at all. Every bit of information about making a particular product was spread across varied spreadsheets, word documents and handwritten paper sheets in 3 ring binders. In some cases it was all contained in the head of one key employee who had been around long enough to learn every conceivable detail about the products manufacture.
Product data management is the system that tries to replace that single key employee, and all the documents as well with a single source of data entry that takes products from creation to shipping to after sales support.
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