Welcome to the second of three articles exploring CD and DVD Drives. Today I?m going to look at CD-RWs, and how to burn CDs.

The first thing to explain about CD-RWs, is that they do not behave, without previous configuration, anything like floppy-disk drives.

Floppy drives can be written to over and over, in what the techies call ?real time?, that is ?as we speak?.

CD-RWs are not like that ? at least not for most of us ? there is a method of use that allows CDs to be used like that, but its quite complex and most of us wouldn?t be using it so I won?t be covering it. Instead, I?m going to look at the most common uses of CD-RWs: To copy data and to copy music.

Both methods require the appropriate software. For Windows XP, there is built in software for data CD writing, but also two major software packages are quite commonly bundled ? Roxio and Ahead Nero.

Using Windows XP built-in software, you simply select the files you want and either drag and drop or copy and paste them onto the CD-RW drive under ?My Computer?.

Using the other packages you must create a ?Data Project?, which sounds very grandiose, before you do anything else, but the concept is the same: You navigate around your PC selecting files you want to copy to CD, and simply drag and drop them or copy and paste them onto the CD-RW drive.

That isn?t it, however. All you?ve done so far is assemble the files you want to copy to the CD, and put them, if you like, in the ?departure lounge?.

Now you must burn the CD with this assembled data, and you do so by selecting the appropriate function, or button, and then the CD will start to be written.

A couple of words of caution are now required: There is a phenomenon called ?Buffer under-run?, which comes about when the CD writing-laser is busy writing data to the CD and suddenly runs out of information to write.

This happens because the computer processor (which we have covered in a previous article) is not ?up to the job? of delivering data to the laser quick enough, and basically the laser stalls, and corrupts the CD, making it unuseable.

Most modern processors are up to the job, and CD-RWs manufactured in the last couple of years are supposedly ?Buffer under-run Proof?).

However, to ensure that you never have a problem, here?s a quick-and-dirty earthling?s guide to ensuring good CD writing:

1. If you are given the option of selecting the write-speed (and many products do provide the option), I would always select a middle speed (ie if you are offered five write-speeds, select the third).

This ensures that you are never writing as fast as the CD-RW laser can work, thus allowing the processor time to keep up with the laser;

2. Don?t do ANYTHING else on your computer while it?s burning a CD. Effectively you will be distracting the processor, which will try desperately to service you and the CD writing process, and In so doing run the risk of not keeping up with the laser.

For good measure I would always close down other applications and stop any music that?s playing, just to ensure that the processor is dedicated to the job of writing my CD;

3. Always cut two CDs; Whilst corruption of data during the write process is a remote possibility, the chances of it occurring twice is even more remote. Burning two CDs pretty much reduces the risk below 0.5 percent.

4. Finally, when the burn process has finished, the CD will usually eject. Be sure that the data is on the CD by pushing it back in and double-clicking the CD icon under ?My Computer?. This simple step ensure that you have the data safely copied to the CD.

Secondly, if you find you have more than one package installed, I would suggest you remove all of them so that you have just one.

My experience tells me that the two programs conflict with each other and the end result is that neither of them work properly.

Though there is little actual proof of this, I would always either remove all packages except the one you want, or else get a qualified technician to do it. Thus you will be sure that there are no other programs contending to use your CD writing capabilities.