To kill a process in Ubuntu Linux, you can use the kill command with the process ID (PID) of the process that you want to terminate.
To find the PID of a process, you can use the ps command to list the currently running processes and their PIDs, or you can use the top or htop commands to view a live updating list of processes and their PIDs.
Once you have the PID of the process that you want to kill, you can use the kill command with the -9 option to force the process to terminate. For example:
kill -9 12345
Replace 12345 with the actual PID of the process that you want to kill.
It is important to note that the kill command should be used with caution, as it can potentially cause data loss or other issues if used improperly. It is generally a good idea to try to terminate a process gracefully using the kill command with a signal other than -9, such as -15 (SIGTERM), before resorting to using -9 (SIGKILL).
You can also use the killall command to kill all processes with a specific name, or the pkill command to kill processes based on their name or other attributes. For example:
killall process_name pkill -u user_name
For more information on using the kill, killall, and pkill commands, you can consult the man pages or use the --help option with each command.