What Is OCR and How Does Optical Character Recognition Work?
If you have ever scanned a physical paper document with an office scanner or smartphone camera, you may have noticed you cannot highlight or copy the text. Here is why, and how OCR fixes it.
Image Pixels vs. Digital Vector Text
A digital PDF created in Word contains font glyph instructions and Unicode character mappings. The computer understands the word "contract" as specific letter codes.
A scanned PDF, however, is simply a photo embedded inside a PDF wrapper. The computer sees only a grid of colored pixels, not words.
How OCR Solves This
Optical Character Recognition (OCR) analyzes the pixel shapes, identifies baseline edges, and matches patterns to recognized letterforms.
The engine then embeds an invisible, selectable text layer directly behind the scanned image, allowing you to highlight, search (Ctrl+F), and copy text.
Summary
OCR transforms static photos of paper into actionable, indexable, and accessible digital documents.
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