The “ls” command in Linux Ubuntu

In Ubuntu (and most Unix-like systems), the ls command is used to list the contents of a directory.

When you type:

ls

…it shows the names of files and folders in the current working directory.

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Common Options:

• ls -l → Long listing format (shows permissions, owner, size, and modification date)
• ls -a → Shows all files, including hidden ones (those starting with .)
• ls -lh → Human-readable file sizes (e.g., 5.2K, 3M instead of just bytes)
• ls -R → Lists contents recursively (includes subdirectories)

Example:

ls -lha

might output something like:

drwxr-xr-x  5 user user 4.0K Oct 27 10:30 .

drwxr-xr-x 15 user user 4.0K Oct 26 08:12 ..

-rw-r--r--  1 user user  220 Oct 27 09:45 .bashrc

drwxr-xr-x  2 user user 4.0K Oct 27 10:00 Documents

-rw-r--r--  1 user user 1.2M Oct 27 10:20 data.txt

Here’s what each column in -l format means:

1. File type & permissions
2. Number of links
3. Owner
4. Group
5. File size
6. Last modification date/time
7. File or directory name