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Support for partitioned media, and thereby the master boot record (MBR), was introduced with IBM [[PC DOS]] 2.0 in March 1983 in order to support the 10 MB [[hard disk]] of the then-new [[IBM Personal Computer XT]], still using the [[FAT12]] file system. The original version of the MBR was written by David Litton of IBM in June 1982. The partition table supported up to four ''primary partitions'', of which [[DOS]] could only use one. This did not change when [[FAT16]] was introduced as a new file system with DOS 3.0. Support for an ''[[extended partition]]'', a special primary partition type used as a container to hold other partitions, was added with DOS 3.2, and nested ''logical drives'' inside an extended partition came with DOS 3.30. Since MS-DOS, PC DOS, OS/2 and Windows were never enabled to boot off them, the MBR format and boot code remained almost unchanged in functionality, except for in some third-party implementations, throughout the eras of DOS and OS/2 up to 1996.
In 1996, support for [[logical block addressing]] (LBA) was introduced in Windows 95B and DOS 7.10 in order to support disks larger than 8 GB. ''Disk timestamps'' were also introduced.<ref name="Sedory_2004_Timestamp"/><!-- TBD: Recheck, if MBR LBA support was really added with 95B/7.1 only, since LBA support in general was added with 95A/7.0 in 1995 already IIRC. --> This also reflected the idea that the MBR is meant to be operating system and file system independent. However, this design rule was partially compromised in more recent Microsoft implementations of the MBR, which enforce [[cylinder-head-sector|CHS]] access for [[FAT16B]] and [[FAT32]] partition types [[Partition type#PID 06h|{{mono|0x06}}]]/[[Partition type#PID 0Bh|{{mono|0x0B}}]], whereas LBA is used for [[Partition type#PID 0Eh|{{mono|0x0E}}]]/[[Partition type#PID 0Ch|{{mono|0x0C}}]].
Despite sometimes poor documentation of certain intrinsic details of the MBR format (which occasionally caused compatibility problems), it has been widely adopted as a de facto industry standard, due to the broad popularity of PC-compatible computers and its semi-static nature over decades. This was even to the extent of being supported by computer operating systems for other platforms. Sometimes this was in addition to other pre-existing or [[cross-platform]] standards for bootstrapping and partitioning.<ref name="Lucas_2003_OpenBSD"/>
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