An early non-volatile magnetic storage device. Developed by Bell Labs researcher Andrew Bobeck in the 1970s, bubble memory was about as fast as a slow hard disk but it held its content without power. As hard disks greatly improved in the 1980s, bubble memory was abandoned even though it was well suited for rugged applications.
Only a couple of square inches in size, a bubble memory module contained a thin film magnetic recording layer, and globular-shaped bubbles (bits) were electromagnetically generated in circular strings inside this layer. In order to read or write the bubbles, they were rotated past the equivalent of a read/write head. See SSD
Bubble memory is conceptually a stationary disk with spinning bits.