Nanny-Level Tutorial: Detailed Explanation of the ls Command in Ubuntu

In Ubuntu, `ls` is a commonly used command to view directory contents. The basic usage is `ls` (displays non-hidden files in the current directory, sorted alphabetically). Its core lies in option combinations: `-a` shows hidden files (including `.` and `..`); `-l` displays detailed information (including permissions, owner, size, modification time, etc.); `-h` works with `-l` to show sizes in units like KB/MB; `-t` sorts by modification time, `-r` reverses the order, `-S` sorts by size, `-d` only shows directory names, and `--color=auto` differentiates file types by color. Combinable options include `-lha` (detailed + hidden + size) and `-ltr` (detailed + time + reverse). It can also view specified paths, such as `ls /home/user/Documents`. Common combinations are `ls -l` (detailed), `ls -a` (hidden), `ls -lha` (detailed hidden size), etc. It is recommended to use `man ls` for more help.