If you’re only planning on administering a WordPress website and are uncomfortable with learning coding, then you won’t ever have to understand what “chmod” is and what it can do. WordPress is designed to be easy to use without having to rely on using terminal commands like “chmod.”
In both the Linux and Unix operating systems, “chmod” is a command that stands for “change mode” which adjusts the permissions needed to access a file or directory. It is the equivalent of a user role in WordPress in that each file and directory on a computer can be viewed, accessed, moved, renamed, or deleted based on whether the user has the right privileges. The “chmod” command changes which privileges are necessary to access and/or modify a given file or directory.
Note: For Windows users, “chmod” is equivalent to “change file attributes.” For Mac users, it is equivalent to the “Get info” general settings for a file.
The “mode” of files and directories is usually designed to protect the files and/or directories from being accidentally overwritten, moved, added to, or deleted. But there may be times when you need to add a new file to a protected directory or make modifications to an existing file. To do this, you’ll need to use the “chmod” command.
The reason you may need to execute the “chmod” command is when you want to install a plugin or make adjustments to your website and need to change the permissions for a given file or directory.
Linux/Unix uses a special syntax to adjust the current mode of a file or directory. Because this is such a powerful command, never use “chmod” unless you are absolutely sure about what you are doing!