83002 is the Terminal process and the 9 means to kill the process. You can use other numbers like 3, which means Quit, or 6, which means Abort. Mostly, though, you’ll be sticking with 9. You can also use the KILL command to kill all running processes, though you should probably never use this command.

To quit (close) a Mac app normally, choose Quit from the app's menu in the menu bar, or press Command (⌘)-Q. If the app doesn't quit, follow these steps to force the app to quit.

How to force an app to quit

• The table below this information shows all open applications on your Mac – including those running in the background. Step 5: Open a new Terminal window and type the command Kill followed.
• Press these three keys together: Option, Command and Esc (Escape). Or choose Force Quit from the Apple menu in the top left-hand corner of your screen. (This is similar to pressing Control-Alt-Delete on a PC.) Then select the app in the Force Quit window and click Force Quit.

Press these three keys together: Option, Command, and Esc (Escape). Or choose Force Quit from the Apple menu  in the upper-left corner of your screen. (This is similar to pressing Control-Alt-Delete on a PC.)

How To Kill A Hung App On Mac

Then select the app in the Force Quit window and click Force Quit.

You can even force the Finder to quit, if it stops responding: Select Finder in the Force Quit window, then click Relaunch.

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How To Kill Hung App On Mac Os

How to force an app to close on your iPhone, iPad, or iPod touch.