Why tmux?
Many developers spend much of their day in a terminal. Whether using it for coding; SSH sessions to remote servers; browsing the filesystem; local tasks such as checking, compiling, or linting code, running unit tests; or even for mail or Internet Relay Chat (IRC), the terminal is one of the most widely used weapons in the developer's arsenal.
tmux is a command-line application that runs within your terminal and turbocharges it. Its powerful features allow for the simplification of many everyday tasks, as illustrated throughout this book. However, the main reason most people use a program like tmux is that it allows you to take a single terminal window and turn it into many virtual windows, each having their own state. It is one in a class of applications called terminal multiplexers (tmux is just a shortening of this term). It has some brethren, but the most prominent is GNU Screen.
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