CD and DVD are two different versions of an optical disk. These two versions of the optical disk are different from each other based on their sizes and manufacturing methods. Both CD and DVD work on optical technology and to retrieve the data from the CD and DVD, we use light especially from the laser. The data in the CD and DVD is stored in the form of bits and a laser beam is also connected in them. With the help of this laser beam, we can easily read the data which is stored in the CD and DVD. The main difference between CD and DVD is given below;

What is the CD?

CD (Compact Disk) is known as the first step to store information and data in the form of digital coding. To store data in the CD, we are using the novel method of coding. It means that we are using a 14-bit coding technique to store data and information in a CD. This 14-bit coding technique is also useful in detecting errors. After the development of the CD, it was accepted at a large scale. Its reason was that it was the low-priced method to store huge amount of information in the digital form.

What is DVD?

DVD (Digital Versatile Disk) can also store information in the digital form. The main quality of a DVD is that it can store information several times larger than the CD. A DVD can render the videos with random access and better quality of the image. A DVD is also prepared from the same material as we are preparing the CD. Anyhow, method and layers of these two discs are different. We can use the DVD from both sides. Therefore, we can say that two CDs are sticking together on a DVD. The main reason behind the larger space of a DVD is that it has dense packing of the bits, it has the shortest wavelength laser and we can store data in both sides.

Key Differences Between CD and DVD

CD and DVD are different from each other in various ways. The key differences between CD and DVD are given below;

Ø Capacity

The first main difference between a CD and a DVD is in their capacity. When a CD was constructed, it was known as the best replacement of the cassette tapes. Nowadays, a CD can store 700 MB of data. For example, if you want to store audio content in a CD, its length should not exceed from 80 minutes. On the other hand, if you want to store video content in this disk, it should not exceed from the 60 minutes. A DVD is also known as an essential optical medium to store digital information and data. The capacity of a standard DVD is up to 4.7 GB. That’s why we are using a DVD to store large files like movies. The capacity of CD and DVD is also known as the biggest difference between a CD and a DVD.

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Ø Use

Before the CD and DVD, we were using cassettes and VHS tapes for data storing. After that, the CD was introduced. The main quality of the CD is that it can’t deteriorate the data even after playing many times. That’s why it gained popularity and it replaced the cassettes and VHS tapes. Anyhow, due to the low storage capacity of this disk, we are using it to store software and computer programs. After some time, DVD was introduced. Due to high compatibility and large storage of the DVD, we are using it to store large files like computer programs and movies. Moviemakers are using DVDs to store their data. As CD has low cost than DVD, that’s why we are using CDs instead of DVDs on music albums.

Ø Playback

Nowadays, we are using two kinds of players. First is known as a CD player and the second is known as a DVD player. A CD player can run only a CD and it can’t run DVD. On the other hand, a DVD player can run a DVD as well as a CD. As CD-disks have lower costs than DVDs, we can run CDs in a DVD player too and we can store the entire music album in a CD, that’s why CDs are more useful for us than DVDs.

Ø Dual-Layer

A DVD is a dual-layer disk and a laser is equipped in a DVD to read the dual-layer. As we can store data on two layers of the DVD, that’s why a DVD has a large capacity than a CD. This dual-layer of the DVD is also helpful for us to retain the resolution and audio quality of the video. That’s why most of the Hollywood movies are produced by using this technique. We are not using this technique in CDs. Moreover, CD players can’t read this dual-layer of the disks.

Ø Formats

A CD is available in just two formats. These two formats of the CDs are CD-R and CD-RW. On the other hand, there are more than half-dozen formats of the DVDs are available. Some essential formats of the DVDs are DVD-R, DVD+R, DVD-RAM, DVD+RW and DVD-RW etc. The old DVD players can’t play all the formats of the DVDs. Anyhow, the modern DVD players can easily play all the formats of DVDs as well as two formats of CDs.

Ø Video Output

All the DVD players have video outputs. It means that when we connect the DVD player with the television, it plays audio as well as video. On the other hand, a CD player doesn’t have a video output because it has only audio output. That’s why when you connect it with your television, it will run only audio and it will not run video.

Ø Purpose

The purpose of creating the CD and DVDs is also different. It means that a CD is created to store only audio and program files. On the other hand, a DVD is used to store a substantial amount of programs, movies and other video files.

Ø Recording Layer

The recording layer is present both in the CDs and DVDs. The only difference is that in a CD, this recording layer is present close to the top of the disk. On the other hand, in the form of a DVD, this recording layer is present close to the middle of the disk.

Ø Pits

Layers of pits are also present both in CDs and DVDs but the only difference is that a CD has a single layer of the pits. On the other hand, a DVD has a double layer of the pits.

Ø Space between loops and pits

The space between the loops of a CD is 1.6mm and the space between the pits in a CD is 0.834mm. On the other hand, in the case of a DVD, the space between the loops is 0.74mm and the space between pits is 0.40mm.

Ø Error Correction Code

No doubt, there is a possibility of the occurrence of errors in a CD and a DVD. If an error occurs in a CD, we can use CIRC and EFMP as error corrections. On the other hand, if an error occurs in a DVD, we can use RS-PC and EFMPlus as error corrections.

Ø Data Transfer Rate

The data transfer rate in a DVD is greater than on a CD. It means that we can transfer data in a CD at the rate of 1.4 to 1.6 MB/sec and we can also transfer data in a DVD at the rate of 11MB/sec.

Ø Channel Bit Length

The channel bit length of a CD is 300 nm. On the other hand, the channel bit length of a DVD is 113 nm.

Ø Damage After the Removal of the Adhesive Labels

If we remove adhesive labels from a CD, it damages its metal layer only. On the other hand, if we remove adhesive labels from a DVD, it will become a cause of imbalance in the spin.

Ø Numeric Aperture and Thickness

Numeric aperture and thickness of a CD and a DVD are also different. The numeric aperture of CD is 0.45. On the other hand, the numeric aperture of a DVD is 0.6. Similarly, the thickness of a CD is 1.2 mm. On the other hand, the thickness of a DVD is 0.6 mm.

Conclusion

Both CD and DVD are known as optical recording mediums. Anyhow, a CD is the best medium to record the audio. On the other hand, a DVD is the best medium to store universal data. Due to the larger storage of a DVD, we can use it to store larger files. On the other hand, due to less storage capacity, we can use a CD to store only audio files and software. The formatting efficiency of a DVD is also 32% greater than the formatting efficiency of a CD.

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Difference Between CD and DVD