Bubble memory is a kind of non-unstable laptop Memory Wave Method that uses a skinny movie of a magnetic materials to hold small magnetized areas, known as bubbles or domains, every storing one bit of information. The material is organized to kind a collection of parallel tracks that the bubbles can transfer along underneath the action of an exterior magnetic area. The bubbles are read by moving them to the sting of the fabric, the place they are often learn by a conventional magnetic pickup, and then rewritten on the far edge to maintain the memory cycling via the fabric. In operation, bubble recollections are just like delay-line memory methods. Bubble memory began out as a promising technology in the 1970s, offering performance just like core memory, memory density similar to onerous drives, and no transferring parts. This led many to consider it a contender for a "common memory" that may very well be used for all storage needs.

The introduction of dramatically faster semiconductor memory chips within the early 1970s pushed bubble into the sluggish finish of the scale and it started to be considered largely as a alternative for disks. The equally dramatic enhancements in exhausting-drive capacity by means of the early 1980s made it uncompetitive in worth terms for mass storage. Bubble memory was used for some time within the 1970s and 1980s in purposes where its non-shifting nature was desirable for maintenance or shock-proofing causes. Bubble memory is essentially the brainchild of a single particular person, Andrew Bobeck. Bobeck had labored on many sorts of magnetics-related projects through the 1960s, and two of his tasks put him in a particularly good place for the development of bubble memory. The primary was the event of the first magnetic-core memory system pushed by a transistor-based mostly controller, and the second was the development of twistor Memory Wave memory. Twistor is basically a version of core memory that replaces the "cores" with a bit of magnetic tape.

The primary benefit of twistor is its means to be assembled by automated machines, versus core, which was almost entirely manual. AT&T had great hopes for twistor, believing that it might enormously cut back the price of pc memory and put them in an industry main place. As a substitute, DRAM recollections got here onto the market in the early 1970s and rapidly changed all earlier random-entry memory programs. Twistor ended up being used only in a number of purposes, many of them AT&T's personal computer systems. One attention-grabbing aspect effect of the twistor concept was observed in production: beneath sure conditions, passing a present by way of one of many electrical wires running contained in the tape would trigger the magnetic fields on the tape to maneuver within the direction of the current. If used correctly, it allowed the stored bits to be pushed down the tape and pop off the end, forming a sort of delay-line memory, however one the place the propagation of the fields was beneath pc management, versus robotically advancing at a set charge defined by the supplies used.

However, such a system had few advantages over twistor, especially because it didn't enable random access. In 1967, Bobeck joined a workforce at Bell Labs and started work on enhancing twistor. The memory density of twistor was a function of the scale of the wires