Where are external commands typically located?

External commands in Linux are typically located in specific directories within the filesystem. The most common locations include:

1. /bin: Contains essential user commands that are required for the system to boot and run in single-user mode.
2. /usr/bin: Contains the majority of user commands and applications that are not required for basic system functionality.
3. /usr/local/bin: Used for user-installed software and commands that are not part of the standard distribution.
4. /sbin: Contains system administration commands that are typically used by the root user.

You can use the which command to find the exact location of an external command. For example:

which ls

This command will return the path to the ls command, indicating where it is located in the filesystem.