About why Linux is divided into a maximum of four sectors of explains

Before someone asked why install Linux when primary partitions + extended partition can only have 4, at that time due to the lack of basic knowledge, cannot resolve the problem, there is now little, now to share with you.

MBR (MasterBootRecorder) main boot sector information, place the hard disk. MBR can be said that the entire hard drive is the most important places, because in the MBR which records two important things: power-management program, and disk partitioned tables (partitiontable). So we made a hard disk partition, that is, modify the partitiontable. Due to the limited capacity of MBR block, so that was originally designed, it was only designed to record four partitions, these partitions are called Primary record (primary partition) and Extended (extended partition), that is, a hard disk can have up to four Primary + Extended sectors, among them, there can be only one Extended, so if you want to partition into four partitions, then it is up to you: P + P + P + PP + P + P + E to partition. Need special attention, if the above situation, 3P + E only three 『 available 』 disk, if you want four are 『 available 』, partitioned into 4P! (as Extended cannot directly be used, you also need to be partitioned into Logical) thinking: if I want to be my big hard disk temporarily partition into four partition, at the same time, there are other space can make me in future planning, how to partition?, by just described, we can know the Primary + Extended only four partition, but if you want more than 5 partition, then you need Extended help. Therefore, in this case, we must not partitioned into four Primary why? if you are a hard drive, but gigabytes of 4 primary share went 15GB, you thought there 5GB can take advantage of? wrong! remaining 5GB cannot use, this is because there are no superfluous partitiontable records area can record, and therefore there is no way to make additional zones, of course, space is also worried about being wasted! so please do note that if you want to partition over more than 4 slot, please remember to have Extended partition, and must include all the remaining space is assigned to the Extended, then the logical partition to planning Extended space.