What is a Master Boot Record (MBR)?

The Master Boot Record (MBR) is a special type of boot sector located at the very beginning of a storage device, like a hard drive or USB stick. It contains two key things: the partition table, which outlines how the disk is divided, and the bootloader, which helps the computer start up an operating system. MBR has been the standard for partitioning disks since the early days of PCs, but it has limitations. It only supports disks up to 2 TB in size and up to four primary partitions. Newer systems often use GUID Partition Table (GPT) instead, which overcomes these limits.