+R, -R, RW, ROM: The confusions behind the disc types

Having computer knowledge is good, obviously because in this IT world you can at least boast yourself at least in front of your friends that you have some knowledge in it. Having computer knowledge is bad, obviously because your friends are always ready to ask you the IT related questions and makes you feel uncomfortable. Worst of all, they will ask you anywhere whether on mobile, at your room, in a café, when you are walking by, when you are sleeping; just anywhere. Few weeks back one of my friends asked me about the meanings of those +R, -R, RW, R you find written on CDs and DVDs. These are the disc formats which create really a big confusion to most of people and to be honest most people just like to ignore these. But ignoring them can call a big trouble for you sometimes. Suppose you recorded some data in a CD RW disc from your office or some songs from your friend’s computer only to find out later that the disc is not supported by your disc drive. It’s better to know these formats to avoid getting into such problems. Let’s look into some of the common types of discs, their capacities and the devices to which they are compatible with.

CD-ROM:
It’s also known as read-only disc which means you can only read data but can’t add or delete data. The general capacities are 650MB or 700MB though now a smaller disc with a capacity of 42MB. It is compatible with almost every device that can read the disc.

CD-R/ CD+R:
You can burn files to this type of disc more than once but you can’t delete the already burned data from the disc. Each time you burn data to the disc a session is created. You must close the session to read the disc in different computer. It is highly compatible with most devices and are found in the same capacities as CD-ROMs

CD-RW/CD+RW:
A CD-RW disc can be burned and erased many times. You can burn files to this type of disc more than once and also you can delete unwanted files from the disc to reclaim space and add additional files. It is found in 650MB capacity and is compatible with many devices but I personally have found that some of the old CD players don’t support this disc.

DVD-ROM:
A DVD, which stands for Digital Video Disc (also called Digital Versatile Disc), can hold more data than a CD. A DVD-ROM can be read several times but data can’t be added or deleted once it is burned. Any devices that can read or burn a DVD disc will easily read this disc. Also note that those devices which can only read CD discs can’t read a DVD disc. In contrast, a DVD disc reading device can easily read a CD disc. A single layer DVD can hold about 4.7 GB of data which is about 7 times more than a CD and dual layer DVD can hold about 8.5 GB of data which is about 13 times more than a CD.

DVD-R/DVD+R:
You can burn files to this type of disc more than once but you can’t delete the already burned data from the disc. Each time you burn data to the disc a session is created. You must close the session to read the disc in different computer. It is highly compatible with most devices and is found in the same capacities as a DVD-ROM.

DVD-RW/DVD+RW:
You can burn files to this type of DVD more than once. You can also delete the unwanted files from the disc to reclaim space. The capacities are similar to a typical DVD ROM. You don’t need to close the session to read this disc in another computer or device. As mentioned above, each time you write your data to a disc, you create a session.

DVD-RAM:
You can burn files to a DVD-RAM more than once. You can also delete unwanted files from the disc to reclaim space and add additional files. DVD-RAM discs can generally only be read by DVD-RAM drives and most of the DVD players and other devices don’t support these discs.DVD-RAMs are found in a number of capacities: 2.6GB, 4.7GB, 5.2GB, and 9.4GB

This information might help you mostly while buying the disc drives to ensure which discs are supported by the drive you are buying and what type of discs should be bought for writing. Also in some situations, you might also write some useful information on a disc only later to realize it is not supported by your disc drive. Having computer knowledge is obviously good in these conditions.

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