There are many different types of CDs and DVDs so that you can easily get confused. We'll try to explain the most common ones for a better understanding. There are many more formats though, you can look them up at Wikipedia if you like.
At this point, you might also want to check which manufacturer produces the highest quality media.
|CD / CD-ROM||Compact Disc (or CD Read Only Memory), very commonly used term. Usually this refers to non-writable discs.|
|CD-R||Writable discs (or CD Recordable). This means that you can only burn data a single time on it, or multiple times when using multisession mode until the capacity is exhausted. You cannot physically delete data (unless you damage the disc and the like).|
|CD-R 74/80/…||The numbers behind CD-R indicate the capacity of the disc. 74 for examplease means 74 minutes of (uncompressed) music (= 640MB). Below this table is a list of all capacities.|
|CD-RW||Rewritable discs (CD Rewritable). You can not only add data, but you can also erase the whole data on disc in oder to put different contents on it. Usually you can erase it a few hundred times. If you want to use this type of disc like a floppy disc, you have to use programs like Nero InCD.|
|DVD / DVD-ROM||Digital Versatile Disc (or DVD Read Only Memory). Basically the same as CD-ROM, however, a DVD typically has a 6 times greater capacity than a CD.|
|DVD-R / DVD+R||Writable DVDs (or DVD Recordable). Basically the same as CD-R with greater capacity. Note that DVD-R (say: DVD minus R) and DVD+R (say: DVD plus R) is a different kind of disc. There is virtually no difference between those types, but it might be the case that your DVD burning device can only burn DVD-R or only burn DVD+R. Most modern devices support both formats equally though.|
|M-Disc DVD+R||Writable DVD+R discs with special properties. By using an inorganic data layer, these discs can preserve data for up to 1000 years (according to the manufacturer). Since usual lasers cannot burn these discs, a drive that supports M-Discs is required.|
|DVD-RW / DVD+RW||Rewritable DVDs (DVD Rewritable). Basically the same as CD-RW with greater capacity. Note the difference between + and -, see DVD-R/DVD+R above.|
|DVD-RAM||Stands for DVD Random Access Memory. It is comparable to a DVD+-RW. However, it has a much higher lifetime (approx. 30 years) and can be erased much more often than a DVD+-RW (at least 10.000 instead of 1.000 times). Also, it has higher data security than a usual DVD. Additional to that you can use it like a floppy disc, if you have appropriate drivers.|
|DVD … DL||Stands for Double (or Dual) Layer. Double layer discs have twice as much disc space than usual DVDs.|
|HD-DVD||Stands for High-Definition Digital Versatile Disc. HD-DVDs are comparable to DVDs with higher capacity, but have already been abandoned by their creators.|
|BD-R||Stands for Blu-Ray Disc Recordable. Basically comparable to a DVD+-R, but has a much higher capacity.|
|BD-RE||Stands for Blu-Ray Disc Rewritable. Basically comparable to a DVD+-RW, but has a much higher capacity.|
|CD … 74||74 minutes of uncompressed audio or ≈650.3 MiB of data (681984000 bytes).|
|CD … 80||80 minutes of uncompressed audio or ≈703.1 MiB of data (737280000 bytes).|
|CD … 90||90 minutes of uncompressed audio or ≈791.0 MiB of data (829440000 bytes). Disc size cannot be detected automatically and disc needs to be burned using the “Overburn” option.|
|CD … 99||99 minutes of uncompressed audio or ≈870.1 MiB of data (912384000 bytes). Disc size cannot be detected automatically and disc needs to be burned using the “Overburn” option.|
|DVD-R (DVD-5)||4.7 GB ≈ 4.38 GiB 1) of data (4707319808 bytes). CDBurnerXP assumes a size of 4706074624 bytes for disc spanning (lower disc sizes have shown in practice).|
|DVD+R (DVD-5)||4.7 GB ≈ 4.38 GiB 2) of data (4700372992 bytes).|
|DVD … DL (DVD-9)||8.5 GB ≈ 7.95 GiB of data (8543666176 bytes).|
|HD-DVD Single Layer||15 GB ≈ 14.0 GiB of data (15076554752 bytes).|
|HD-DVD Dual Layer||30 GB ≈ 31.1 GiB of data (33393473536 bytes).|
|BD Single Layer||25 GB ≈ 23.3 GiB of data (25025314816 bytes).|
|BD Dual Layer||50 GB ≈ 46.6 GiB of data (50050629632 bytes).|
If you are not familiar with the meaning of GB, GiB, MB etc, read a wikipedia article on that matter. Basically vendors specify capacities (of hard drives for example) using GB/MB which results in a higher value compared to GiB/MiB. However, Windows will usually only tell you the GiB/MiB value, despite the fact that it writes GB/MB as unit behind the value.
How do you know whether or not your drive can burn a particular type of disc?
The most accurate information will probably be in the manual of your drive. However, most drives also have a few icons at the front which help to identify its abilities.
Note that there might be modified icons like for “CD-RW Highspeed” which allows writing suitable CD-RWs with higher speed or DL which refers to Double Layer DVDs.
Maybe you find it hard to decide which type of disc to use for each purpose. Here is our recommendation.
|Audio-CD for music player etc.||CD-R with 80 minutes is the default choice. Rewritable discs will not work in every audio player.|
|Short term data storage, just for “transport”||CD-RW for small and DVD+-RW for large amount of data. This allows you to use the disc multiple times.|
|Backups, long term data storage||DVD-RAM. They have a quite high lifetime and data security. Or even better yet, if you can afford it: M-Discs|
|Movies||Usually DVD+-R, unless you want to use the same disc multiple times. A movie won't fit on CD. There is such a thing as an SVCD (method to burn movies to CD), but this results in a rather low-quality movie and multiple discs are required.|
|Photos||Those will usually fit on a CD-R or CD-RW (use the latter one if you intend to reuse the disc for other purposes later).|