Most of the files are stored or sent in a compressed file format which makes them take up less space that is what we call it as zip. They are "zipped" but cannot be used by the computer in their compressed format. In order for your computer to use them, you have to decompress or "unzip" those files this is what we call it as un zip.
Example : Suppose if you want to send any of your 2 or 3 photos by mail to your friend .You will try to attach those files into your mail . But some times if files size exceeds your mail doesn't allow to send a mail. In such cases you can compress those photos into small size file by using some software that is what we call it as ZIP.
If once your friend receive those photos your friend has to unzip those files by using some software.
Usually in order to unzip we will use winzip or winrar softwares . But there are some free softwares as well.
If you type "7 zip" in google you will get some link . Please try to down load that software. And install that software in your PC .
Then create a folder name call it as "my photos" place all your 3 photos into that folder . Then right click on that folder select 7-zip it will navigates to another sub menu call it as Add to "my photos.zip" click on this .
Consequently you will be able to see a compressed or zipped file call it as my photos.zip
Now you can send this file to your friend by a mail.
