What is the meaning of the permission to execute in a directory in an operating system?

Execution permission for a directory in an operating system means the ability to "enter" the directory and access its contents.

If a user has execute permission on a directory, they can:

• Use this directory in a path to access files or subdirectories.
• Execute commands like cd to change into this directory.

Without execute permission, even if read permission is granted, the user cannot enter the directory or access files inside.

For example:

• r (read) — allows viewing the list of files in the directory.
• x (execute) — allows entering the directory and accessing files if their names are known.

Thus, execute permission on a directory controls the ability to navigate and access its contents.