tmux is terminal multiplexer. More simply, using tmux, you can have multiple terminal sessions, or panes, within a singular window. Each pane is running its own independent terminal session.

Before getting into how to use tmux, it is important to note all commands in tmux are trigged by a prefix key followed by a command. The tmux prefix key is C-b. 
The C- notation means press and hold the Ctrl key. 

Together C-b means to press the Ctrl & b keys at the same time.

  • Install tmux on a Personal Machine

    Linux

    Use the following Terminal command to install tmux (depending on your Linux OS):

    sudo apt-get install tmux
sudo yum install tmux
sudo dnf -y install tmux

    macOS

    Use the following Terminal command to install tmux:

    brew install tmux

  • Navigating tmux Panes & Windows

    Launch tmux (Start a Session)

    To launch tmux, open your terminal window and execute the following command:

    tmux

    Panes

    Creating multiple panes in one window allows you to see what you're working on across multiple terminal sessions at the same time. 

    Managing Split Panes

    Here is where you will begin to use your <prefix> + commands.

    Create a Horizontal Split Pane (Left/Right)

    prefix + %

    (Press your prefix - Ctrl + b - then release and press %)

    Horizontal Split Screen in tmux.

    Create a Vertical Split Pane (Top/Bottom)

    prefix + "
    Horizontal and Vertical Split Screen in tmux

    Navigating Through the Panes

    To navigate through the Panes, use your prefix + arrow keys.

    prefix + up arrow
prefix + down arrow
prefix + left arrow
prefix + right arrow

    Closing Panes

    Use the exit command to close a specific pane.

    To completely close the pane:

    prefix + X

    Windows

    tmux also allows you to create multiple windows, or similar to having multiple virtual desktops!

    Create a New Window

    prefix + c

    Renaming Your Window

    If it helps you stay organized, you can rename your windows at anytime:

    prefix + ,

    You will be prompted at the bottom of the screen to rename the window.

    Navigating your Windows

    Go to Previous Window

    prefix + p

    Go to Next Window

    prefix + n

    Go to Specific Window

    If you've created so many windows it becomes difficult to navigate with p and n alone, you can go to a specific window by going to the session number in your window's name in the status bar:

    prefix + sessionnumber

    Closing Windows

    To close the current window:

    prefix + &

    Restart tmux

    To kill all existing tmux sessions and start fresh:

    tmux kill-server

  • Session Handling with tmux

    One of the perks of using tmux is its ability to maintain sessions in the background. If you are done with your work for the day, you can keep the session alive in the background for later use. 

    Detach Sessions

    Use the detach command to detach your current session so you can shutdown:

    Detach All Windows

    prefix + d

    Detach Specific Window(s)

    You can select specific windows to detach with:

    prefix + D

    Restart Detached Sessions

    To view a list of the tmux sessions running in the background:

    tmux ls

    Use the attach command to get started on your session (where # is the session number):

    tmux attach -t #