What Are the Storage Capacities of a CD ROM & a DVD?
The specification for CD-R has been around since 1988. However, CD burners as we know them weren't widely available until the late mid-'90s. It did not take long for units to become cheaper and cheaper and then faster and faster. There are three common CD-R capacities at this time. DVD-R has been around since 1997, but easily obtainable cheap home recorders did not become widely available until around the year 2000. There are only two capacities for recordable DVD discs.
Other People Are Reading
-
Original CD-R capacity
-
The first CD-R commercially available was the 650MB CD-R, which is still sold. It holds 74 minutes of CD audio or 650MB worth of data.
700MB CD-Rs
-
Around the year 2001, 700MB CD-Rs started becoming available. They can hold 80 minutes of audio or 700MB of data. Previous to these discs, people used what was known as "overburning" to put more data on a 650MB CD-R than was intended. Reliability was spotty at best. Retail 700MB CD-Rs hold their data fairly reliably.
-
Mini-CD-Rs
-
By the mid-2000s, 80mm CD-Rs became widely available. They hold all of 21 minutes of audio, or 186MB of data. Their common use in retail was for "CD Singles," but they didn't catch on. They also have spotty compatibility. While most CD-ROM drive trays can accommodate the 80mm CD, some cannot read them.
Single Layer DVD-/+R
-
Single layer DVD-/+R discs hold the same amount of data, which is 4.7GB. They are called single layer because they have only one recording surface.
Dual Layer DVD-/+R
-
Dual layer DVD-/+R discs also hold the same amount of data at 8.5GB per disc. They are called dual layer because like a retail DVD, they have 2 recording layers. If you want to make a full 1:1 copy of a movie you own, you must use a dual layer DVD-/+R to do so.
-
References
- Photo Credit Image by Flickr.com, courtesy of John Ward
