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Indeed, the act of creating computer programs—or "software"— has become a major preoccupation of computer scientists. At the University of Pennsylvania, null designers, J. Presper Eckert Jr. and John W. Mauchly, had to alter the wiring manually, almost as if they were telephone operators rearranging the plugs on a switchboard, when they wanted to give the machine new instructions. Now, as the result of the development of an increasingly sophisticated hierarchy of computer languages such as FORTRAN, COBOL, BASIC and APL, computer users are able to give the machine instructions that are more and more like spoken English.
Extraordinary as today's computers are, they will probably seem like dumbbells compared with those on the horizon. Computers may be improved, for example, by a charge-coupled device (CCD) developed by Bell Labs; it stores packets of electrical charge in movable chains, like the clothing on the automatic racks in dry-cleaning establishments. As the charges pass by a station, they can be "read." Experimental CCDs that store more than 65,000 bits per chip have been built. To cram still more information onto a chip, engineers are experimenting with a tool even more precise than photolithography: beams of electrons, which can be aimed and controlled by computer as they trace out the miniature circuitry. Another Bell innovation is the magnetic-bubble memory, in which microscopic pockets of magnetism ("bubbles") are created in a semiconducting material. Prodded by an external electric or magnetic field, the bubbles move along orderly pathways; as they pass fixed stations, the presence or absence of bubbles is read as coded information. A 250,000-bit experimental bubble memory has already been produced. In the future the contents of an entire encyclopedia, film library or record collection may be stored on a chip.
Looking in another direction, scientists at IBM and elsewhere are seeking to improve not only the computer's memory but its logical functions as well. One approach stems from predictions made in 1962 by a young British graduate student named Brian Josephson, who shared a Nobel Prize for the work. His ideas involve a physical phenomenon called electron tunneling. At temperatures close to absolute zero (—459.69° F.), he theorized, an electrical current—or flow of electrons—can tunnel through barriers that would ordinarily restrain them.
Scientists quickly realized that Josephson's theory could form the basis for wondrous superconducting switching devices. Depending on the presence or absence of a small magnetic field, electrons would cross from one side of the barrier to the other, as in a transistor, but with a significant difference: the amount of current in a Josephson junction would be infinitesimally small. That would keep down the amount of heat generated, and thus the circuitry could be even more tightly packed. By the late 1980s, IBM scientists envision tiny computers, refrigerated inside tanks of liquid helium, that operate a hundred times as fast as today's machines.