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Basic commands in terminal computing
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In here, we want to demonstrate basic commands when doing work in the powershell/terminal as well as in the jupyter notebook.

NOTE, that when running terminal commands in the jupyter notebook, you need to add a :code:`!` in front of the command, so e.g. :code:`!ls`.

File and Directory Management
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* :code:`ls` - shows the content of your current directory.

::

    ls
    ls -l    # Detailed list (long format)
    ls -a    # Show hidden files


* :code:`cd` - Change directory.

::

    cd /path/to/directory
    cd ~     # Go to home directory
    cd ..    # Go up one directory level


* :code:`pwd` - Print working directory (shows your current directory).

::

    pwd


* :code:`mkdir` - Create a new directory.

::

    mkdir new_directory


* :code:`rmdir` - Remove an empty directory.

::

    rmdir directory_name


* :code:`cp` - Copy files or directories.

::

    cp source_file destination_file
    cp -r source_directory destination_directory   # Recursive copy (for directories)


* :code:`mv` - Move or rename files or directories.

::

    mv old_name new_name
    mv file /new/location


* :code:`rm` - Remove files or directories.

::

    rm file_name
    rm -r directory_name    # Recursive remove (for directories)
    rm -f file_name         # Force removal (use with caution)


File Viewing and Editing
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* :code:`cat` - Display the contents of a file.

::

    cat file_name


* :code:`less` -  View file contents one page at a time.

::

    less file_name


* :code:`touch`` - Create an empty file or update the timestamp of an existing file.

::

    touch file_name


* :code:`tail` - Showes the last lines of a file 

::
    
    tail file_name
    tail -n N file_name     #shows the last N lines of the file


Search and Find
===============

* :code:`grep` - Search inside files.

::

    grep "search_term" file_name
    grep -r "search_term" directory   # Recursive search

    
* :code:`find` - Search for files and directories.

::

    find /path -name "file_name"


Compression and Archiving
=========================

* :code:`tar` - Archive or extract files.

::

    tar -cvf archive_name.tar directory_name   # Create a tar archive
    tar -xvf archive_name.tar                  # Extract a tar archive
    tar -czvf archive_name.tar.gz directory_name   # Create a gzip-compressed tar archive
    tar -xzvf archive_name.tar.gz                  # Extract a gzip-compressed tar archive