[Day 1] 4. File System

!4. Partition of Hard Disk.png

File System

A file system is responsible for organising and managing files on a storage partition. It dictates how files are stored, accessed, and managed on the disk.

Key Concepts

1. **Data Block **:

   • Stores the actual content of the file.
   • The default size is 4 KB, but it can be configured during formatting.

2. File Control Block (FCB, inode in Linux):

   • Stores the metadata (information) about the file.
   • Metadata includes file name, size, permissions, timestamps, and more.

3. Master File Table (MFT, inode list in Linux):

   • The area where File Control Blocks are stored.
   • It contains the metadata for all the files in a partition.

4. Volume Control Block(super block in Linux):

   • Stores information about the volume or partition, such as:
     • Label: Name of the partition.
     • Size: Total size of the volume.
     • Filled/Empty Space: How much space is used or available.
     • Keeps track of free data blocks to allocate for new data.

5. Boot Sector(Boot Block in Linux):

   • Contains essential programs needed for booting the system. It is divided into two main components:
     • Bootstrap Program: Initialises the system and loads the boot loader.
     • Boot Loader: Loads the operating system into memory.

What is a File System?

A file system is essentially a way of organising files on partitions. It provides the structure for storing and retrieving files on the disk.

Types of File Systems

Depending on the operating system or device, different file systems are used:

• NTFS (New Technology File System): Used by Windows.
• ext (Extended File System): Commonly used by Linux.
• HFS (Hierarchical File System): Used by mac OS.
• FAT32 (File Allocation Table 32): Often used in pen drives and external storage devices.

Even though the contents of files may be the same across different systems, the organisation and structure of the file system vary.