In the video world, the DVD-ROM disc is quickly overtaking the traditional VHS tape. The DVD-ROM disc is also poised to take over the reign of CD as the media of choice for virtually every new computer on the planet. But what about recordable DVDs?
Unfortunately, things are still a little tenuous in the world of recordable DVD standards. Luckily, the competing formats correspond pretty closely to the world of recordable CDs. Here are a few acronyms you need to know:
* DVD-RW: DVD-R is short for DVD-recordable. (Note the dash before the R; it's pretty important.) Like your old friend the CD-R disc, a DVD-R disc can be recorded only once. However, the DVD-R can hold a whopping 4.7GB per side of the disc, for a total of 9.4GB of data on a double-sided disc. DVD-R is the darling of the video-editing crowd, because it allows you to record a disc that you can use in a standard DVD player. Naturally, the DVDs that you create with a DVD-R drive can't be read on a standard CD-ROM drive (but you can burn regular CD-R and CD-RW discs).
On the rewritable side, the DVD-R disc format is called DVD-RW. These discs can also store 4.7GB, and you format them much like you format a CD-RW disc. Any DVD-ROM drive should be able to read a DVD-RW disc. Unfortunately, not all DVD players can read DVD-RWs, so if you're an up-and-coming Hollywood type that's interested in producing your own movie discs, you should stick with the DVD-R standard (which is compatible with all DVD players).
Pick DVD-R/W if you're looking for the highest level of compatibility with all DVD-ROM drives or you're distributing discs to others.
* DVD+R/W: The other independent DVD standard, DVD+R/W, is widely available as well. This more recent format is being touted by an entirely different group of computer hardware manufacturers. DVD+R discs and DVD+RW discs can store 4.7GB, and a DVD-ROM player can read both types of discs. Again, however, you run into the same problem - DVD+R discs are compatible with most DVD players, but DVD+RW discs aren't widely supported by DVD players. Plus, DVD-R/W and DVD+R/W are incompatible.
Pick DVD+R/W if you're looking for compatibility with the latest DVD-ROM drives or you want to spend a little less on media.
* DVD-RAM: Finally, you have good old DVD-RAM - a rewritable disc that can store as much as 9.4GB of data by using both sides. (A double-sided DVD doesn't have a standard label; printing can appear only around the spindle hole.)
DVD-RAM is well established, and no "plus" format is competing for fame and fortune. DVD-RAM is a great option for storing those huge digital video files, and because DVD-RAM discs are reusable, they're the best media for backing up hard drives. Note, however, that most DVD-ROM players can't read DVD-RAM discs, so use one of the other DVD formats if you're recording something to distribute to others.
Choose DVD-RAM if compatibility with DVD-ROM drives is not an issue, such as when you're creating backups or discs that you read only on your computer, and you want to rewrite the largest amount of data on an existing disc.
You may be wondering whether you need a rewritable DVD-R/W drive, a DVD+R/W one, or a DVD-RAM model? Why not get all three? Unless you've been hanging out with the good folks at the lottery commission, that's probably not an option. You can, however, find many drives on the market that can use both DVD-R/W and DVD+R/W.
However, the good news is that the relative strengths of all three types of recordable DVD media make it easy to decide which one you need. Check out Table 1 for the scoop.
Table 1 Will DVD-R/W, DVD+R/W, or DVD-RAM Escort You to the Ball?
Media Type Can Be Read in Reusable/Rewritable? Media Cost DVD Players
DVD-R Almost always No $2 per disc (4.7GB)
DVD+R Almost always No $2 per disc (4.7GB)
DVD-RW Usually not Yes $4 per disc (4.7GB)
DVD+RW Usually not Yes $3 per disc (4.7GB)
DVD-RAM Usually not Yes $15 per disc (4.7-9.4GB)
Although DVD-R and DVD-RW are separate categories in the table, it's getting harder and harder to find a drive that records only DVD-R - and the same holds true for DVD+R/W. This trend mirrors the development of CD-RW technology. Try finding a drive that burns only CD-Rs these days!
Besides being incredibly informative, Table 1 uses the words almost and usually, which don't show up in many definitive tables. Why? The answer lies not in today's recorders, but rather in yesterday's DVD-ROM players: Four distinct generations of DVD-ROM players have existed since their introduction in late 1997, and each succeeding generation has a better chance of reading DVD-Rs, DVD+Rs, and DVD-RAMs.
The result is a big question mark. Because of the wide disparity in manufacturers, it's hard to tell whether the DVD-ROM player you have now reads any type of burned disc. If you're using a DVD+R or DVD-RAM, you have the best chance with a DVD-ROM player manufactured since early 2001. If you're using DVD-R, you have the best chance with a DVD-ROM player made after late 1999. You can, however, read a commercially manufactured DVD-ROM movie disc in either type of recorder.
If your DVD recorder is limited to one format or the other, take care when you're buying DVD media! Make sure that you remember which type of discs your recorder can burn - you'll be deluged by the choices on store shelves, and it's easy to mistake DVD-R discs for DVD+R discs if you're not careful.
http://tech.yahoo.com/gd/understanding-the-difference-between-dvd-rw-dvd-rw-and-dvd-ram/153155;_ylt=AmSUZQrdRR4apib0Dfw15ssSLpA5
