Toy enigma that challenges ingenuity. Solutions to puzzle may require recognizing patterns and creating a particular order. People with a high inductive reasoning aptitude may be better at solving these puzzles than others. Puzzles based on the process of inquiry and discovery to complete may be solved faster by those with good deduction skills. A popular puzzle toy is the Rubik's Cube, invented by Hungarian Ernő Rubik in 1974. Popularized in the 1980s, solving the cube requires planning and problem-solving skills and involves algorithms. There are many different types of puzzles, for example a maze is a type of tour puzzle.
D-3 (video) D-3 (video) D-3 is an uncompressed composite digital video videocassette format invented at NHK, and introduced commercially by Panasonic in 1991 to compete with Ampex's D-2. It uses half-inch metal particle tape at 83.88 mm/s (compare to D-2's 19 mm and 131.7 mm/s). Like D-2, the composite video signal is sampled at four times the color subcarrier frequency, with eight bits per sample. Four channels of 48 kHz 16–20 bit PCM audio, and other ancillary data, are inserted during the vertical blanking interval. The aggregate net (error corrected) bitrate of the format is 143 Mbit/s, and because the codec is