Hi Joni,
OCR stands for Optical Character Recognition. It is used to recognize text in PDFs. For example, say you scan a piece of paper with text on it and save as a PDF. That PDF does not have any computer recognizable text on it- it is just an image or picture of the piece of paper. Running OCR will turn the text on the PDF into recognizable text that can then be searched, edited, etc.
In terms of searching for a Word if the PDF already has recognizable text then you can just use the Search feature in Acrobat without the need to run OCR. If the PDF is not searchable then you cna try running OCR then try searching for the word of interest.
Hope this helps,
Dimitri
WindJack Solutions
www.pdfscripting.com
www.windjack.com