Difference between DVD+R, DVD-R, DVD+RW, DVD-RW

There are DVD+R, DVD+RW, DVD-R, DVD-RW, and even DVD-RAM! So what is the difference between all of these different names, aren't all DVDs the same? Well, it's not quite that simple.

Let's first start with the most obvious difference: some have R and some have RW. The R stands for recordable, while the RW stands for rewriteable.

The main difference between DVD-R and DVD-RW, or DVD+R and DVD+RW is that the R disc formats can only be written to once, and then it is only readable and can't be erased for the rest of its digital life. While RW discs are can be written to and erased many times, they are both readable and writeable.

Now, Let me explain the difference between the "-(minus)" and the "+(plus)".

DVD-R and DVD+R are two competing technologies that use different formats. No single company owns either DVD format and both technologies have their advantages.

DVD-R/RW was developed by Pioneer. Based on CD-RW technology, it uses a similar pitch of the helix, mark length of the 'burn' for data, and rotation control. DVD-R/RW is supported by the DVD Forum, an industry-wide group of hardware and software developers, and computer peripheral manufacturers. The DVD-R format has been standardized in ECMA-279 by the Forum, but this is a private standard, not an 'industry' ISO standard like the CD-R/RW Red Book or Orange Book standard.

DVD+R/RW is also based on CD-RW technology. DVD+R/RW is supported by Sony, Philips, HP, Dell, Ricoh,Yamaha, and others, and has recently been endorsed by Microsoft. DVD+R/RW is not supported by the DVD Forum, but the Forum has no power to set industry standards, so it becomes a market-driven issue.