urxvt:tldr:21b39

This command launches the urxvt terminal emulator, with the following options:

1. --hold: It tells urxvt to keep the terminal open even after the executed command finishes. By default, the terminal would close immediately after the command completes, but with --hold, it stays open, allowing you to view the command's output or interact with the terminal further.
2. -e ${command}: This specifies the command to be executed in the terminal. ${command} is a placeholder that indicates where you would replace it with the actual command you want to run. For example, if you want to execute the command "ls -l", you would replace ${command} with ls -l, resulting in urxvt --hold -e ls -l.