Differences between DVD-R, DVD-RW, DVD+R, DVD+RW, and DVD-RAM: A Comparison of Recording Formats and Playback Compatibility

When looking for recordable DVDs at stores or online, you will see many similar names such as "DVD-R," "DVD-RW," "DVD+R," "DVD+RW," and "DVD-RAM." Furthermore, labels like "For Video," "For Data," "CPRM compatible," "DL," and "Video Mode" can make it difficult for first-time buyers to understand the differences.

A particularly common misconception is that the minus and plus signs indicate quality, or that simply saving video files to a DVD-R means they will definitely play on a DVD player. In reality, "-" and "+" are symbols denoting different standard families, not quality rankings. This article provides a multifaceted overview of each standard's origins, capacity, rewrite limits, usage, and playback compatibility.

1. Four pillars for understanding recordable DVDs

Recordable DVDs are easier to understand when categorized by the following four points:

• Physical standard: DVD-R, DVD+R, DVD-RW, DVD+RW, DVD-RAM, etc.
• Recording frequency: Write-once (cannot be erased) or rewritable (can be erased and reused).
• Content format: DVD-Video, VR mode, PC data, video files, etc.
• Playback conditions: Player compatibility, CPRM, finalization, region, video signal standard, etc.

Even if the physical standard is compatible, the disc cannot be played if the content format is unsupported. Conversely, even if the file format itself is supported, the disc cannot be played if the device cannot read the disc.

2. What is DVD-R?

DVD-R is a write-once disc that can generally only record data one time. A standard single-layer disc holds 4.7GB and has been widely used for video storage, distributing photos and documents, and recording on home recorders. Since it has been in widespread use since the late 1990s and has many compatible devices, it is a standard with relatively high compatibility among recordable DVDs.

However, once recorded, content cannot be erased to restore the disc to a blank state. While it may be possible to append data if there is free space, the disc might become unreadable by other devices depending on the appending method or session state. To view it on a DVD player, it is standard practice to create it in DVD-Video format and finalize it at the end.

3. What is DVD-RW?

DVD-RW is a rewritable type that allows content to be erased and recorded repeatedly. It is suitable for temporary TV recordings and applications where content is frequently updated. The capacity is generally 4.7GB.

While convenient, it may not be readable by older DVD players because its reflectivity and recording structure differ from those of DVD-R. Additionally, home recorders may offer a choice between DVD-Video mode and VR mode, and players that do not support VR mode will not be able to play the disc.

4. What is DVD+R?

DVD+R is a write-once disc developed by a different standards organization than the one behind DVD-R. Its typical capacity is 4.7GB. "+R" does not mean it is "superior to -R." On compatible drives, mechanisms focused on recording management and ease of appending data were adopted.

Most modern devices support both DVD-R and DVD+R, but some older players or specific models may only support one. If a device's specification sheet says "DVD±R," it usually indicates compatibility with both series.

5. What is DVD+RW?

DVD+RW is the rewritable type in the "plus" series. It can be erased and reused, making it suitable for editing and appending data. While similar to DVD-RW, its recording management method is not identical.

In some environments, users may not need to be overly conscious of the finalization process, but this does not mean it will play the same way on every player. If you intend to watch it on another device, follow the instructions of the device used for creation to perform compatibility processing.

6. What is DVD-RAM?

DVD-RAM is a standard that prioritizes direct access to required locations, much like a hard drive, for frequent rewriting. It has strengths in data preservation reliability and rewrite durability, and in the early days, cartridge-based products were also used. It was adopted for TV recording and backups at one time.

On the other hand, its compatibility with general DVD players is limited. Even if it looks like a DVD, there is a high probability that it cannot be played if the player's specifications do not explicitly list DVD-RAM, so checking before purchase is essential.

7. Comparison table of the 5 standards

8. What is the difference between "For Video" and "For Data"?

If the standard and capacity are the same, the basic recording structure is not necessarily significantly different between "For Video" and "For Data" discs. However, in Japan, "For Video" discs have been labeled with indicators regarding CPRM support for recording copyright-protected digital broadcasts and compensation systems.

When saving digital terrestrial broadcasts from a recorder, choose a CPRM-compatible "For Video" disc as specified by the recorder. If you are only saving PC documents or photos, a "For Data" disc is fine. Please prioritize the supported standards mentioned in your device's instruction manual over the usage labels.

9. What are DVD-R DL and DVD+R DL?

DL stands for Dual Layer, meaning double-layered on one side. It can record approximately 8.5GB, which is more than the standard 4.7GB, and is used for long-duration videos or large-capacity data. However, devices that support DVD-R do not necessarily support DVD-R DL.

10. What is finalization?

Finalization is a closing process that prepares a recorded or created disc so that it can be read by other players. A non-finalized disc may be playable on the recorder that created it, but may appear as "No disc" or "Read error" on other DVD players.

Check your device's instruction manual before operating, as it may be impossible to add more data after the process. For discs like DVD-RW, finalization can sometimes be reversed depending on the mode and device.

11. Copying video files alone does not make a DVD-Video

Dragging and dropping MP4, MOV, MKV, etc., onto a DVD-R usually results in a "Data DVD." If the DVD player does not support the file format and the video/audio codec, it will not play. If you want to play it like a commercially available movie, you must use authoring software to create the DVD-Video structure.

Even with the same extension, internal compression methods can differ. For example, H.264 or H.265 might be used inside an MP4 container. It is important not to judge compatibility based solely on the extension.

12. Order of checks when playback fails

1. Check if the disc surface is DVD-R, DVD-RW, DVD+R, DVD+RW, DVD-RAM, or DL.
2. Check if that same standard is listed in the player's specification section.
3. Determine if it is a commercial DVD, a TV recording, a DVD-Video, or a homemade data DVD.
4. If it is a TV recording, check the CPRM and recording mode.
5. Check if it has been finalized on the device used to create it.
6. If it is a video file, check both the extension and the codec.
7. Check the disc for dirt, scratches, warping, or degradation over time.

13. Choosing a compatible model

Frequently Asked Questions

Summary

DVD-R and DVD+R are write-once standards, DVD-RW and DVD+RW are rewritable, and DVD-RAM is a standard resistant to frequent rewriting. However, matching the standard does not guarantee playback. You must verify DVD-Video or data DVD formats, recording mode, CPRM, finalization, DL support, and video codecs.

The most reliable method is to check the specification sheets of both the recorder and the playback player, and choose a disc supported by both. For important videos you wish to keep for a long time, do not rely on just one disc; create backups on a separate medium.