disk-partitioning

disk-partitioning

Date: 2026-01-23

Intro

In simple terms, we know mounting as inserting eg a usb drive into your computer
What really happens is that the system attaches a folder to the usb drive so that you can access its files. This happens to all other storage devices like a CD-ROM or a hard drive or even a floppy disk ( :) outdated) .The folder which the system attaches storage device is the mount point
The main hard drive partition is mounted as “/” which is the root.
CD-ROM - /media/cdrom
USB drive - /mnt/usb
NOTE - Suppose i wish to mount the CD-ROM which is located at /dev/sr0 to the mount point or folder /media/cdrom I need to be careful and understand that the files and subdirectories on CD-ROM will fall under /media/cdrom and any files that were originally at /media/cdrom will not be visible although they are present. When i unmount the CD-ROM the original files at /media/cdrom will become visible again.
sudo mount /dev/sr0 /media/cdrom - command for mounting (This is crucial only for servers and crucial operations)

A partition is like a section or part of a hard drive. Analogy, a house being the hard drive and rooms being partitions where each partition stores different stuff in it.
In linux, hard drives are located in the /dev/ folder and are named as follows:

In the past, different types of hard drives had different names but this changed because of hotplug which is a new feature which unifies device management
lsblk / sudo parted -l - command for listing all the drives and partitions
df -h - command for viewing disk usage
Every external storage has its block device location at /dev/
Use gparted app on ubuntu to see how your drive has been partitioned even for those who have dual-booted you will still see how the windows and linux have used the space

Traditionally, a hard drive is made up of many platters. On each platter there are 512 byte sectors making up a track. Many tracks stacked on top of each other make the cylinder. Data is stored on these 512 byte sectors.
Nowadays , disks with 4k byte sectors are being manufactured for fast performance as compared to the old 512 bytes
In the past, computers described hard drives using Cylinders, Heads, and Sectors (CHS).
Modern systems use Logical Block Addressing (LBA), where every sector gets a number.
For huge hard drives, an advanced version called LBA48 was introduced to handle more sectors.
Master Boot Record (MBR ) is the older partitioning system that supports up to 4 primary partitions and a maximum disk size of 2 terabytes.

GPT (GUID Partition Table) is the newer standard, supporting up to 128 partitions by default and larger disk sizes. GPT was designed for use with a UEFI-based system