Wirebook › Glossary › Partition table (MBR vs GPT)
What is a partition table (MBR vs GPT)?
In one sentence: The small map at the start of a drive that says where each section begins; MBR is the old kind many cars and TVs need, GPT the newer one computers use.
A little more
Before a drive can hold a file system like FAT32, exFAT or NTFS, it needs a partition table: a tiny map at the very start of the drive saying where each section (partition) begins and ends. A computer reads that map first, then looks inside each section for the file system. There are two kinds of map. MBR (Master Boot Record) dates from the early 1980s, allows up to four main sections and can't describe a drive bigger than 2 TB. GPT (GUID Partition Table) is the modern one, with room for 128 sections, huge drives and a backup copy of the map at the end of the drive in case the first gets damaged.
Newer computers usually make GPT when they format a drive. That's fine for computers, but many car stereos, older TVs and some cameras only understand MBR, so a stick can have a perfectly good FAT32 file system and still not be seen. Reformatting it with the MBR scheme (Master Boot Record in a Mac's Disk Utility, or Convert to MBR Disk in Windows Disk Management) fixes it. Changing the map erases what's on the drive, so copy files off first.
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