A scanned PDF usually contains page images rather than editable text. Optical character recognition identifies letters and words so the content can be searched or converted.
Start with a clear scan
Straight pages, strong contrast, and sufficient resolution produce better recognition.
Run text recognition
Choose the correct document language and preserve the original scan while OCR is applied.
Review the result
Names, numbers, columns, and unusual fonts deserve extra attention. OCR accelerates transcription but still needs human review.