In the early 1980s, many manufacturers introduced smaller floppy drives and media in various formats. A consortium of 21 companies eventually settled on a a.k.a. "Micro diskette", "Micro disk", or "Micro floppy", similar to a Sony design but improved to support both single-sided and double-sided media, with formatted capacities generally of 360 KB and 720 KB respectively. Single-sided drives shipped in 1983, and double sided in 1984. What became the most common format, the double-sided, high-density (HD) "1.44 MB" (actually 1440 KiB) disk drive, first shipped in 1986. The first Macintosh computers use single-sided -inch floppy disks, but with 400 KB formatted capacity. These were followed in 1986 by double-sided 800 KB floppies. The higher capacity was achieved at the same recording density by varying the disk rotation speed with head position so that the linear speed of the disk was closer to constant. Later Macs could also read and write "1.44 MB" HD disks in PC format with fixed rotation speed.