Android How to

What is Android File Structure and Directory Structure

Android File Structure
Written by Kelly Houstan

Android-file-system most folks are familiar with the file layout on Windows and are really happy navigating the Windows file system. Windows basically uses a drive letter for each and every physical drive or partition that is C: drive. Just read this article to know all about What is Android File Structure and Directory Structure. Let’s start!

Note: A Physical drive will actually have at least 1 partition but can actually have more than one. This is true for both Windows and Android as well.

What is a Disk Partition?

Disks can also be subdivided into smaller disks called partitions. Partitions actually appear and can be used because if they were separate physical disks. If you guys insert a USB drive into your windows machine it shows up as a disk along with an assigned drive letter.

Although windows show a disk icon the disks can be partitions of a single physical disk. Each and every disk partition has a root directory that contains files and folders (directories). The root of the C drive is C:\ and also of the F drive is F:\ etc

What is Android File Structure and Directory Structure

Android File System Structure

Android basically uses the Linux file system structure that also has a single root. The diagram below actually shows the structure too.

Android File Structure

The system partitions and directories are also protected and unless your device is rooted, you guys don’t normally have access to these although some file managers will also show them actually.

Physical disks and partitions basically appear under the root as a directory and do not actually have a drive letter as in Windows. Android does not normally come along with a default file manager, and so you guys will have to install a file manager app. Such as Astro file manager, in order to locate and manage files and folders.

The sdcard and ext-sd card Partitions

The sdcard partition is actually the main storage area for user data and files. It also contains App settings and data as well. The sd card partition basically exists even though you may not have an external sd card as well.

It is basically the internal partition.

If you guys open the sd card directory you will see something like this:

Android File Structure

Note: Partial listing only

These files and directories basically contain your pictures, films, downloads, etc as well as App data and settings also. You guys can view these files from your PC through connecting your device to a PC via a USB cable. You can also transfer files between your device and a PC just using this method.

The ext-sd card partition will only visible if your device supports external storage actually. Most of the time using a microSD slot. External sd cards use either the FAT, FAT32, or exFAT file system formats as well. Most of the devices support FAT and FAT32, however, support for exFAT is limited. The choice of the file system is governed via the partition size as follows:

Card Type

Card Type File System

Max Capacity

SDHC FAT32 32GB see Note

Note: Windows format size limit of 32GB. Can be larger but need to format via external tools. Windows XP could format FAT32 Volumes up to 128 GB as well.

Android File Associations

Just as with other operating systems such as Windows, Android will also use an App in order to open a specific file type, which is denoted via the extension. Such as, if you guys try to open a pdf file it will normally use Adobe reader (if installed) in order to open the file.

  • In order to open a file, you will normally have to locate the file using a file manager.
  • Just tap on the file to open it.
  • If the file type doesn’t already have an App associated along with it you should be prompted to select between the available Apps.
  • The option to always use that App sets it as the default app for that file type as well.
  • If you guys set it as the default App you will not be prompted again unless you delete the association.
  • In order to remove an association, you have to remove it from the App itself.
  • So if the pdf files open with adobe reader and you also want to change that:
    • Head to Settings>Apps>Select Adobe reader,
    • Then head to the Launch by default section and then Clear defaults

The next time you guys try to open a pdf file you will be prompted to select an App.

Android File Managers

If you guys search the Google play store, then you will find many file managers. Which App is actually the most suitable relies on what you want to do. You should bear in mind that more features or functionality isn’t always better actually. File managers such as ESF have lots of functionality including:

  • Built-in FTP client
  • Task Manager
  • Cloud storage client etc

However for many, this is a bit of an overkill, and so you guys might consider installing one of the simpler file managers. Such as file manager and Astro file manager as well.

File Downloads

When you guys download a file using Google Chrome or another browser App the file is saved in the download directory. You guys can access the directory contents via a shortcut in the Apps folder (if provided). You can also use a file manager in order to locate the folder called download. It is under your primary storage actually (called sdcard)


Alright, That was all Folks! I hope you guys like this article and also find it helpful to you. Give us your feedback on it. Also if you guys have further queries and issues related to this article. Then let us know in the comments section below. We will get back to you shortly.

Have a Great Day!

Also See: How to Download Google Voice for PC, Windows, and Mac

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Kelly Houstan

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