Computing machines can be dated back to the advent of the abacus, a wooden rack holding two horizontal wires with beads strung across them. Several different types of arithmetic operations could be performed when these beads were manipulated. Another early calculator, later called Napier's Bones, made its debut in the early 1600's. This device, invented by Charles Napier, consisted of a series of rods that could be used to perform multiplication. The first digital calculation machine was built by Blaise Pascal in 1642. ...

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• Grade Level: High School

Single sided DVD's can hold 3.7 GB. ... It requires a DVD-ROM drive installed in a computer, and DVD-ROM drives can play DVD-Video. DVD-Video is the movie format. ... DVD-R is a write-once version used for creating masters, and DVD-RAM is the official rewritable DVD sanctioned by the DVD Forum. ... DVD-R/W is also a rewritable version, but is more an extension to DVD-R than a competitor to DVD-RAM. ...

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