What is OCR?
Optical character recognition or better known as OCR is a technology that allows your computer to take files that you have scanned, and turn them into something more useful. Scanned files only show up as images and there is not much you can do with them. However, if you use an OCR engine and run these documents through them, they will become text-searchable and editable. Meaning, you can practically treat them as a word document.
How to get PDFs?
PDFs are becoming more and more popular and it has become the format for documents that most companies are going with. In order to get a PDF as your final product, you will need to get your hands on a PDF converter. This will enable you to turn the files that you have scanned and OCRed into PDF format which is what you ultimately want. The best way to go about it is to implement a solution that will be able to provide OCR for you and PDF conversion.
If you are looking for a OCR engine and a PDF converter separately, you will probably have a lot to choose from. However, if you want a solution that can handle both tasks, you will have a much smaller selection. In my experience, CVISION's PdfCompressor is the best product available out there right now. It has high accuracy OCR and it can compress files up to 100x. You can download a free trial to see if the product is right for you. If you have additional questions, feel free to contact them directly.