Filesystem Hierarchy

Root Paths	Description
acct	Contains the Cgroup (Control Groups) information, which is used for resource management and accounting.
apex	Holds the APEX packages, a container for packaging and managing libraries and apps in a modular way.
audit_filter_table	Manages audit rules for logging and monitoring system activities for security and compliance.
bin	Contains binary executables, essential command-line tools, and utilities for the system.
bugreports	Used for storing system bug reports, logs, and diagnostic information.
cache	Temporary storage for application cache files, used to speed up app startup and operation.
config	Stores configuration files and permissions for various system components and apps.
d	Debug file system, providing access to kernel debugging and diagnostic information.
data	Primary storage for user data and application data, including databases, preferences, and files.
data_mirror	Used for mirroring data in certain scenarios, like during seamless system updates.
debug_ramdisk	Contains the ramdisk image used for debugging and diagnostic purposes.
dev	Represents device files that provide access to hardware components and peripherals.
dpolicy_system	Specific to device policy management, handling security and policy enforcement.
efs	Contains sensitive information related to mobile communication, like IMEI and network details.
etc	Holds configuration files and scripts for the system and applications.
init	Contains the initial startup scripts and binaries that initialize the system at boot time.
init.container.rc	Startup scripts specifically for initializing containerized or isolated environments.
init.environ.rc	Defines environment variables and system properties during the boot process.
keyrefuge	Secure storage for cryptographic keys and related security parameters.
linkerconfig	Configuration files for the dynamic linker, controlling how executable binaries find shared libraries.
lost+found	Used by the file system to store recovered files during file system checks (fsck).
metadata	Stores metadata used by the system for various purposes, like encryption keys for file-based encryption.
mnt	Mount directory, where various file systems and storage devices are mounted and accessed.
odm	Vendor-specific configurations and files, part of the device's original design manufacturer data.
odm_dlkm	Contains dynamic kernel modules specific to the original device manufacturer.
oem	Stores OEM (Original Equipment Manufacturer) specific files and configurations.
omr	Reserved for future use, often related to system updates or modular system components.
optics	Typically used for storing camera calibration and configuration data.
postinstall	Holds scripts and files executed after system updates to finalize installation.
prism	Specific to certain devices, used for enhanced UI or system functionalities.
proc	Virtual file system providing access to kernel and process information at runtime.
product	Contains system files and apps provided by the device manufacturer, similar to system but for product-specific components.
sdcard	Mount point for the external SD card, used for additional storage.
second_stage_resources	Resources loaded in the second stage of the boot process, like fonts or themes.
sepolicy_version	Stores information about the SELinux policy version and configurations.
storage	Root directory for user-accessible storage, both internal and external.
sys	Provides access to system and device information through the sysfs filesystem.
system	Contains the core Android OS files, including system apps and libraries.
system_dlkm	Holds dynamic kernel modules for the system, extending kernel functionality.
system_ext	Stores system extensions, additional modules, and components outside of the base system partition.
vendor	Contains vendor-specific binaries, libraries, and apps, separating them from the core Android OS.
vendor_dlkm	Vendor-specific dynamic kernel modules, enhancing or adding hardware support functionalities.