When you scan any Document page, it cannot be edited because you get Image file as output. Now, for making changes in it fro further use- It has to be re-typed so, to avoid and reduce your effort of doing the same typing work again, here are some open source freeware application which can convert scanned document images to editable text documents (more probably DOC or MS Word file)
These softwares are better called as OCR (optical character recognition softwares). This technique is more useful office work which can save time and for other important documents like Project reports, Certificates, etc. where you can get same format of design and fonts used.
2. OCR Desktop
3. Simple OCR
With SimpleOCR, you could easily and accurately convert that paper document into editable electronic text for use in any application including Word and WordPerfect. Not only is SimpleOCR up to 99% accurate, it is 100% free. Download
It handles images with mixed text and graphics (Manual or Auto Zoning) and tolerates skew and uneven lighting. Multiple text output formats, including searchable PDF and HTML can be obtained. It can read 11 different languages and Includes built-in, full featured Text and Image WYSIWYG Editors. Download
Web – Service (installation free)
Lastly, If you don’t prefer downloading and installing any software on your system then you may go for online webservice WeOcr Tesseract Web Interface. Here you need to upload any image file and get output file as text document to be used anywhere.