Which command will list all files, including hidden ones, in a directory?

The command that will list all files in a directory, including hidden ones, is 'ls -a'. In Linux, files or directories that start with a dot (.) are considered hidden and are not shown in the default output of the 'ls' command. By adding the '-a' option, the command modifies its behavior to display all files, including those hidden ones. This makes 'ls -a' an essential command for users who need to see configuration files or other hidden items present in a directory.

The option 'ls -l' provides a long listing format of files, showing details such as permissions, owner, size, and last modification time, but does not include hidden files unless used with the '-a' option.

The 'ls -h' flag is often used in conjunction with the '-l' option to show file sizes in a human-readable format, but it does not affect the visibility of hidden files.

The 'ls -r' command lists files in reverse order, but similarly to 'ls -l', it does not include hidden files unless combined with the '-a' option. Therefore, for listing all files, including those that are hidden, 'ls -a' is the correct command to use.