PDF vs DOC

A PDF file can not be altered but a word document can be.  Also a PDF file can be opened by all operating systems while a word document has to be opened in word.

Compressing files

Compressing files into zip folders is a very useful tool for various reasons.  If the folder is needed to be moved or sent somewhere, compressing it into a zip file means that it is a smaller file to be moved.  It also allows you to keep any formatting that the folders and files already have.  For example if a folder has folders and files inside it, by compressing it into a zip file, the formatting will be the same when the folder is unzipped.  To zip a folder, you select it then right click.  You then select 'send to' then 'compressed 'zipped' folder'.  This will make the folder into a zip file.  To unzip, simply double click on the file.