DVD-R is more compatible but DVD+R burns more reliably and could be considered superior.

The DVD-R format was developed by Pioneer in the autumn of 1997. It is supported by most DVD players, and is approved by the DVD Forum.

In 2002 a new format was developed called DVD+R (or "plus" R). Created by a coalition called the DVD+RW Alliance, this format uses a number of improved technologies that, while generally unnoticeable to the end user, make a more reliable technology. One example is the ADIP system of tracking and speed control used by DVD+R being less susceptible to interference and error than the LPP system used by DVD-R, which makes the ADIP system more accurate at higher speeds. In addition, DVD+R(W) has a more robust error management system than DVD-R(W), allowing for more accurate burning to media independent of the quality of the media. Additional session linking methods are more accurate with DVD+R(W) versus DVD-R(W), resulting in fewer damaged or unusable discs due to buffer under-run and multi-session disks with fewer PI/PO errors.

However, because the DVD-R format has been in use since 1997, it has had a five-year lead on DVD+R. As such, older or cheaper DVD players (up to 2004 vintage) are more likely to favour the DVD-R standard exclusively, and when creating DVDs for distribution (where the playing unit is unknown or older) the DVD-R format would normally be preferable.

DVD - was created about 10 years ago by Pioneer for their DVD players
DVD + was created about 10 years ago by Phillips for their DVD players.

Nowadays all DVD players playback both formats so there is no difference. However, if you have a 10+year old DVD player, check the brand of it and what type of DVD it plays either + or