The later versions of Microsoft Office has the word document extension as .docx instead of the older extension .doc.Suppose if you want to open a word document with .docx extension but you don’t have the latest/compatible version to open them,there are different ways to view them.
View using older Microsoft office – Microsoft Office Compatibility Pack
Microsoft has a compatible pack to view newer version documents in older version office.The Microsoft Office Compatibility Pack can be downloaded from here
View using Google Docs
The document can be uploaded to Google docs and viewed.Thus no softwares have to be installed.
View using Open Office
Open Office is a open-source office suite.By installing Open Office the documents can be viewed
View using on-line tools or converters