When you first scan a printed page to PDF, it creates a document that contains no actual text, just an image of text. Lacking any recognizable text, it does not allow interaction with reading tools, and is also difficult to read on a mobile device.
In a few short steps, software such as Adobe Acrobat Professional, Abbyy FineReader, or OmniPage can take an image-only PDF and make it "Searchable" using a process called Text Recognition, or Optical Character Recognition (OCR). The resulting document has text that you can interact with using a variety of technologies.
Benefits of a searchable PDF include the ability to:
- Search text
- Select text
- Highlight text
- Create a Table of Contents
- Listen to text