ABOUT ZIP FILES
A zip file is just a container for digital content. Putting several books in one zip file makes them easier to download.
You can save the zip file to any directory you want on any device you own.
When you open a zip file, you can specify where to save the files it contains.
Opening and 'unpacking' a zip file is easy. In Windows you can just double-click the zip file or right-click on it and choose 'open'. It may be a bit different for Mac but I am sure it's just as easy.
You won't have any problem. If necessary, just google 'how to open a zip file' and find the info relevant to your device. You'll see it's very easy and takes literally seconds.
- - -