The syllable ya at the end of the mantra denotes an offering. Thus the mantra Om Namah Sivaya actually means I offer to Siva a respectful invocation of His Name, and not merely I respectfully invoke His Name. Om Namah Shivaya mantra is sung by devotees in prayers and recited by yogis in meditation.
Short for Short for DVD-Recordable, a recordable DVD format similar to CD-R. A DVD-R can only record data once and then the data becomes permanent on the disc. The disc can not be recorded onto a second time. There also are two additional standards for DVD-R disks: DVD-RG for general use, and DVD-RA for authoring, which is used for mastering DVD video or data and is not typically available to the general public.
Out of these two most popular ones are DVD-R and DVD-RW. Both allow users to record and store media files such as music or movies and run on all devices with DVD drives. The major difference between them lies in the number of times they can be used. Whereas DVD-R is known as readable DVD, DVD-RW is a rewritable DVD. This means that you can store files only once in a DVD-R and cannot erase and record another file on it, DVD-RW allows the user to erase and record information multiple number of times. Amazingly, the quality of modern DVD-RW is such that one can record and reuse them almost a thousand numbers of times.