Connecting and disconnecting from a tmux session

Tmux (Terminal Multiplexer) is a free and open source software that allows you to open multiple terminal windows in a single console. It allows users to run multiple commands simultaneously in different terminal windows within a single session, as well as move freely between windows and customize their sizes and positions. Tmux allows you to work with the terminal more efficiently, making it more flexible and convenient to use.

What is a tmux session?

Tmux has features such as saving session state between restarts, splitting windows into multiple panes, managing command history, mouse and keyboard shortcuts, customizing themes, and many others.

It can be used both on a local network and via remote access, allowing sysadmins to manage networks and servers more efficiently and securely. Tmux is available for many Unix-like operating systems, including Linux, macOS, and FreeBSD.

A tmux session is a logical grouping of open terminal windows. Each session can contain multiple windows and panes, which can be freely moved and resized independently of each other. When you create a new tmux session, it starts in a terminal and allows you to multitask, i.e. run multiple commands at the same time and display their results in different windows. 

Tmux saves the state of each session, even if you close the terminal, disconnect from the server, or reboot the system. This allows you to continue working where you left off even after you reboot the session. In addition, tmux allows you to switch between sessions, create new windows within the current session, manage windows, panes, assign keyboard shortcuts, and much more.  In general, using sessions in tmux greatly simplifies working with the terminal and increases productivity.

How to attach to a session?

To attach to an already running tmux session, you need to run the following command in the terminal:

tmux attach -t <session name>

where `<session name>` is the name of the session you want to attach to.

How to detach from a session?

To detach from a tmux session and leave it running in the background, execute the following key combination: Ctrl-b d. This command will take you out of the tmux session and into the shell, while tmux will remain running in the background. 

If you want to kill the tmux session entirely, press `CTRL + b` then enter the command `:kill-session`. This will kill all windows and panes associated with that Tmux session.