- 5 - Executable code is composed of sequences of binary digits (zeros and ones). Each digit is called a “bit”, and eight-bit sequences are called “bytes”.3 A computer program can be written onto a magnetic disk or tape by encoding its particular executable code on the surface of the disk or tape.4 That magnetic recording allows the computer processor to read the executable code and to perform the specific tasks directed by the code. Generally, the cost of a blank tape, similar to one upon which the computer programs acquired by petitioner were placed, was less than $25 during the years in issue. An encoded computer program can easily be transferred or copied onto additional blank tapes and disks, resulting in identical reproductions of the program. A computer program can also reside on media other than magnetic tapes and disks, such as punch cards and CD-ROMs 3 For example, in the American Standard Code for Information Interchange (ASCII), the binary representation for the letter “A” is 01000001, and the binary representation for the letter “Z” is 01011010. 4 The surface of the computer disk or tape is magnetically encoded with the executable code by magnetizing the crystals or particles in the recording medium corresponding to the sequence of zeros and ones making up the binary system of executable code. For example, under the “nonreturn to zero inverted” (NRZI) encoding method, every zero is represented on the disk or tape by a magnet pointing in a certain direction, and every one by a magnet pointing in the opposite direction. The amount of information contained on a disk or tape is a function of the magnetic recording density of the disk or tape. The information on the disk or tape is interpreted by the computer when the magnetic bits are converted into electrical signals.Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Next
Last modified: May 25, 2011