When Microsoft released Office 2007, it changed the extension of the of the file. All files on your computer have an extension, whether you see them or not. Typically a program that you run will be a .exe extension, a picture could have a .jpg, .png, .gif, etc extension. In Office 2003 and previous versions the extensions for documents were .doc and .xls for excel. When Office 2007 was released, they changed the extensions to .docx and .xlsx. It is the same for Office 2010. So when someone sends you a document created in the newer version of office, you may get an error message when trying to open it.
If you have Office 2003 or earlier you can download a converter for your Office installation that will allow you to open these newer version documents. Download the file converter from Microsoft’s website. If you have the earlier versions of office, I recommend just installing the converter anyway and you’ll eliminate the issue before it even starts.
A PDF is the extension for “Portable Document Format” (you have no idea how much it irritates me when someone says “PDF Format”). I typically convert something to a PDF when I want to send it to someone, and I don’t want to lose any of the formatting of the original document, or allow them to edit the document at all. When I send a resume to someone I will convert my resume to a PDF, or if I’m going to send a document to someone I know that doesn’t have Microsoft Office (like my brother the Apple Fanboi).
To create a PDF you usually have to have the full version of Adobe Acrobat installed on your computer, which is a very expensive program. With Office 2007 you can create PDF’s by downloading this free plugin from the Microsoft website. Office 2010 natively has this functionality.
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