What Are Computer File Systems

If you’ve been around computers a little, you may have heard about the file system, but what is that exactly?

A computer file system is used to organize files & data in your computer’s non-volatile memory or hard drive in a hierarchy of nested folders. It’s typically organized in a tree data structure, with one parent folder being the hard drive & other folders existing in subfolders below that.

If you need a bit more than that to really understand what a file system is and how you can use it, please read on.

Computer File Systems in Depth

If we talk about what a file system is from the perspective of the computer, there are a lot of details that don’t really matter to the average user, which confuses the whole topic.

If we break it down from the point of view of the average user, all of a sudden, the file system is easy to understand, and it’s useful to know about. It can actually help you in your day-to-day computer use.

A file system allows you to organize and store files on your computer hard drive. They are organized in a system of folders that create a tree-type structure. The main folder or root folder is represented as your hard drive. All of the other folders in the root folder are considered subfolders.

That being said, they’re usually just called folders. Any folder in the file system can hold files and subfolders of its own. This is a great system for searching and sorting files and folders. Without the file system, all of the data on your computer would just be lumped together on the hard drive without a way to reference it or look it up easily.

What file and folder naming restrictions exist?

The naming conventions used typically follow a system where folders are named after topics or projects while files are given names to represent the actual work in the file. However, it would be best if you also stayed within a few guidelines regarding naming. For example, several punctuation marks can’t be used when creating a file or folder name:

Some names are reserved that you can’t use. The chances that you will accidentally pick one of them are pretty low, but I’ll include them here so you have an idea of what they are.

If you’re interested in more naming restrictions, you can find these and more on Microsoft’s site here.

My go-to separation marks are either a plain space, an underscore, or a dash. Even though most punctuation marks have been taken away, that’s still enough to be effective.

File & folder naming tip

When picking names, you want to try and come up with something short but representative. One of the ways that I try to keep my names short is to use something called camel type. It’s a technique used in writing code to make a name with no spaces.

Camel type looks like this:

• aFileName.pdf
• aFolderName
• myResume.docx

As you can see, it makes it very easy to eliminate spaces in a file or folder name while keeping them easy to read.

Additional file features

Files can either be read, written to, or executed in the case of program files. Each file has certain configuration permissions that allow users to either read, write or execute a file based on their permissions. It can be handy to have control over that.

In Windows, it’s a bit clumsy how it has been organized. In Linux and Unix, the solution has been implemented rather well. It’s easy to see a file’s permission level and make changes to it if you have an adequate security profile.

File extensions are a Windows tool for understanding more information about the file itself. Unix and Linux operating systems don’t have them and rely completely on the file permissions as assigned. That’s not to say they aren’t used. They aren’t necessary.

In Windows, the file extension is necessary for the operating system. Still, in modern versions of Windows, since the user doesn’t need to see the file extension anymore, it has been turned off by default. The operating system reads it and assigns an icon instead-but strictly speaking, the file extension is now hidden.

If you want to see the file extensions, you can re-enable them by opening any folder, selecting ‘View,’ and checking ‘File name extensions.’

Operating system files and folders

Within the file system, certain folders are dedicated to the operating system. Operating system files and folders should be considered off-limits. You don’t want to be playing around with your operating system files, creating an error, or deleting something important, inadvertently breaking your operating system.

It’s also a common new user mistake that while you’re clicking around in the folder structure, you end up briefly holding onto a folder and dragging it into a neighboring folder. If that happens to your collection of operating system folders, again, your computer will likely need to have the whole operating system reinstalled.

It’s best to save navigating and playing around in the operating system section of your hard drive until you’re proficient enough not to make a catastrophic mistake.

Other folders hold user data and user files. These are areas where you can read, write, and execute files with relative comfort. This is where you can create new files or folders in a manner that suits your needs. If you accidentally delete something or make the folder dragging mistake, you can either restore the file from the recycling bin or poke around until you find the missing folder.

Searching for files and folders

Most modern file managers allow you to search the file system for files and folders. Files and folders can be indexed, making them easier and faster to search. A search algorithm is only as good as the supporting metadata or information that the search function can access.

To change your search index settings, go to the Settings gear on the Start menu, open ‘Search,’ and click on ‘Searching Windows.’ That will let you expand the indexing if that suits you.

A word of caution, I would respect the excluded folders list unless you really have a specific reason not to. Windows typically doesn’t save data to those locations, so leaving them out is probably the right choice.

How do I navigate my file system?

It used to be that the only way to navigate the file system was to open a command prompt and type commands. For example, you had to type a file path followed by Enter to open folders or a file name followed by Enter to open files.

However, most people don’t find that very easy or intuitive, so graphical alternatives were developed to help make them more accessible. This is also partly why Windows, Unix, and Linux with graphical user interfaces were invented.

But having a graphical interface wasn’t enough. An additional piece of software needed to be developed to support working directly with the file system—a program known as a file manager.

In Windows, we know this as Windows Explorer or Explorer. If you’re interested in learning more about Windows Explorer, I have an article on that here. Apple iOS has the Finder. Linux has a multitude of file managers available, giving Linux users a choice.

However, did you know that you can also get different file managers for Windows? Some of which offer some interesting features for people who are trying to accomplish certain things. For most PC users, sticking with Explorer is probably the best bet, but if you’re adventurous, you can always try some of the different options for yourself.

What are the different types of file system?

There are several different files systems, but seven are worth covering for the average computer user.

1. Disk file system

A Disk file system is the most common files system because it exists on hard drives and other long-term storage devices. It’s comprised of the typical tree-like structure and can hold multiple layers of folders and files.

2. Flash file system

A flash file system is optimized to leverage the strengths of a flash memory device like a USB stick or SD card. Their use is, of course, limited, especially since the disk file system often gets extended to removable media like thumb drives and memory cards.

3. Database file systems

Database file systems are organized using features of the various files rather than their location so that you can search the database by a certain feature set. A great application for this type of file system is in a company with many drawings or corporate documents that they want to search for a given system or author.

4. Transactional file system

The transactional file system exists within the microcosm of a single piece of software. It’s the file system that a piece of software sets up for itself when it gets installed. Thus, it gets set up in a single move and is used on a transactional basis as the software gets used. Naturally, therefore, it must get maintained during updates or the application of extensions.

5. Network file system

A network file system is a file system that is accessed across a network. It can be accessed by more than one machine, so priorities and resource sharing become an issue. Usually, this involves specialized technology leveraging something like FTP or NFS.

6. Shared disk file system

The shared disk file system is often realized with network shares or shared drives like you may see at work. Usually, these shared drives are accessed across a network, meaning shared access is an issue here. Often, they get added to your computer using a process called “Mounting.” You mount network drives. Once it has been mounted, you can access it like an additional hard drive.

7. Flat file system

The flat file system has all but gone extinct. It was more of a common system during the days of floppy drives. As it sounds, a flat file system is flat with only one folder with files in it.

What is a file in a file system?

A file in a file system is a digital representation or marker created to hold information about the data it’s for. The file marker holds the name of the file, the size of the file, and the location of the file on the hard drive. Other details like when it was created are also available.

An interesting property is that it allows you to control access to the file through the read/write/execute permissions, as discussed above. You can copy files, paste files, or create shortcuts to them so you can jump to the file from somewhere else in the file system.

Examples of files include the portable document format file or PDF file, which uses the .pdf extension in the Windows world. Adobe created the PDF file, and for a long time, it was a proprietary format. Then Adobe changed it to an open format, and now all software vendors are capable PDF document creators.

If you’re interested in more information on PDF files, I have an article about them here. Another example is a Word document file that uses the extension .docx and holds a reference to a text document created by Microsoft Word.