When optical drives started to become the norm in home computers, all of a sudden there were two types of CD-Rs for sale, the data kind and the "music" kind.

As to the question of whether or not a CD labeled as a "music" disc is safe to write data to or not, the answer is yes.

Are they as reliable as "regular" data CD-Rs? I’ll answer that in a moment.

Bear in mind there literally is nothing that makes any CD-R a "music" disc. It’s just a marketing term. Any writeable CD-R can be a "music" disc and any "music" disc can have data written to it instead of audio tracks.

As far as the reliability of a "music" disc goes, that’s where you start to see the real differences.

Concerning reliability, a "music" disc is not as reliable as a data disc because they typically fail what I call the see-thru test.

The see-thru test is this: How transparent is the disc? If you hold it up to a light, can you see right thru it easily? And if so, how easily?

The more transparent a disc is, the less aluminum there is, the less reliable the disc will be in the long run – because you’re got more plastic than aluminum at that point. It will (not might) degrade faster.

To note: Truly good data CD-Rs have little to no transparency at all.

The only reason anyone ever buys "music" discs for data use is because they’re dirt cheap. However there are a few uses for those cheap discs:

• They’re good as throw-aways that you can give to friends (ex: burn a Linux distro on a cheapo disc, give it away..)
• They’re good for game disc backups. For example, I have an old game called Jedi Academy but I don’t use the original discs. Instead I copied them for my own personal use and use those for gameplay. And if the copies screw up, no big deal. I just make more.

It also should be noted "music" discs usually have a maximum write speed of 32x. That’s as fast as they’ll write and no faster.

So the only real differences is that "music" has an inferior life span and write speed compared to traditional data CD-Rs.

If you need some throw-aways, go ahead and buy a few.

But don’t use them as a primary backup.