Backing up on CD
When backing up on CD, you must decide whether to use CD-RWs or CD-Rs. I use both types. However, I use one for long-term backups and one for short-term backups. The one thing you should keep in mind when doing backups, wheather on a hard drive, floppy, or CD you can't name two files or folders the same name. For example, if you have a folder on your CD named MY FILES and you want to backup MY FILES again onto the same CD, it will overwrite (CD-RW) or delete (CD-R) the original MY FILES folder. The only difference between the overwriting of the folder on the CD-RW and the overwriting on the CD-R, is that you will lose the amount of space the original folder occupied on the CD-R. The CD-RW will reuse the space the original folder occupied.
I use CD-RW when I want to back something up regularly and don't need to save old copies. For example, if I was to download pictures on one backup and then change those pictures (ie. remove red eyes) before the next backup, I would not need to save the earlier pictures. In this case, I would want the backup to overwrite the older files with the newer files of the same name.
I use C-R when I want to say multiple copies of files. For example, if I was working on a document for technical support, I may make changes to this document all the time. I may after a month realise the changes I made for the last month were not what I really wanted and wish to go back. When saving backups to CD-Rs, I can do that. The only thing is that you have to be careful not to name the folder or file the same name on the same CD as mentioned before. In this case, I created a folder named with the date of the backup. I then move all the files I want to backup in this folder and then backup the newly created folder. This way, when I look on the CD named “Technical Documents”, I will see lots of folders with different dates and know when each one was backed up.