By following this simple tutorial you will be able to back-up desired google documents onto your computer.
1. After going to your Google Docs, check the boxes of the files you want to back-up.
2. Next select Export, which is located under the More Actions option above your docs.
3. A window will pop-up and ask you if you would like to Compress and Download the selected files, hit Continue.
4. After the Compression is complete you will be asked to save the files. Hit OK.
5. Once the download is complete you will recive a zip file of the files you selected earlier. This zip file contains all of our files inside it and is compressed(takes up less space on your computer). However if you only backed-up a single file, it will not be in a zip.