DVD+R is a format for optical data storage. It is similar to, but incompatible with, the older DVD-R standard. A DVD+R is a write-once optical disc with 4.7 gigabytes (GB) of storage, generally used for non-volatile data storage or video applications.

A DVD-ROM should be able to read all formats of cd's. Including regular music cd's (CDA), CD-R (RW), DVD-R (RW).

you can try copy the contents of a recorded DVD-R to a DVD-RW

Yes, you need to insert a bland DVD disc, either DVD-r or DVD+r is ok, before you burn movie to DVD. Generally speaking, DVD-r is more compatible than DVD+r.

DVD-R is the best

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