Q: What is the use of these Partition.
I am runnig os x yosemite 10.10.5
Earlier i installed Ubuntu and for installing ubuntu i installed rEFInd software.
After i did my work then i just uninstalled both (Ubuntu and rEFInd).
Then i installed windows 10 and then i uninstalled windows 10.
My recovery partition was gone so i installed the recovery.
now i am only running mac os x 10.10.5
so i wanna know what is the use of these partition all of them
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *251.0 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS YOSMITE 250.1 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
MacBook Pro with Retina display, OS X Yosemite (10.10)
Posted on Sep 22, 2015 10:19 AM
There are no odd, unexpected or unusual partitions here. The disk0 is the physical disk, and disk1 (EFI console and boot-related bits), disk2 (your data) and disk3 (the recovery partition) are partitions on the physical disk. That's typical of most OS X systems.
If you have any data in any partition(s) here that you wish to preserve, make one or more backups before proceeding.
The following will erase all data...
If you want to wholly reset your entire disk0 disk environment and erase all files across all partition — this will erase all files and all data — then create an OS X Yosemite installer on external storage, and boot from it, and then use Disk Utility from that to erase the entire internal disk using Disk Utility, and continue onward to install Yosemite. Yosemite will partition your disk appropriately.
Again, this sequence erases all partitions and all data on the entire disk.
If you have more than the installer and your to-be-entirely-erased internal disk around, then either disconnect the other device(s) present to avoid a mistaken erasure, or be extremely careful about which disk device you erase lest the wrong disk be clobbered.
You're using the diskutil list command to get some general details on partitioning. If you want more details about the design of GPT partitioning and related topics, then use the following command:
sudo gpt show /dev/disk0
Posted on Sep 22, 2015 1:20 PM