Docx is the extension of files created after Office2007 version;

The difference is that the 2007 edition has some new functions and typesetting styles. If you want to keep them. Doc format, you will lose these new styles.

So, if you want this file. Documents that are completely opened on most computers are saved as documents; If you want to keep some styles unique to the 2007 version, please use docx.

Since it is a graduation thesis, the style of the article is not complicated, but it needs universality. It is recommended to save it in doc format.