Many trading partners still send purchase orders, acknowledgments, packing lists and invoices as PDFs, spreadsheets or email attachments. Someone has to read each one and key it into the ERP. That manual step is slow, error-prone and invisible to the rest of the process: the document exists, but the transaction behind it does not until a person creates it.
OCR vs IDP: optical character recognition (OCR) converts an image of text into machine-readable characters. It tells you what the page says, not what it means. Intelligent document processing (IDP) adds classification and extraction, often with machine learning, to identify the document type and pull out fields such as the purchase order number, items, quantities and totals.
Going beyond OCR means going beyond extraction. A digitized invoice still needs to be checked against the purchase order and receipt, matched to the right supplier and order, and converted into the format your ERP expects. Without that business validation and matching, document digitization simply moves typing errors into your systems faster. Done well, it lets non-EDI trading partners take part in the same process as EDI ones.