After even one ls command in a shell prompt, the terminal window you are working in can begin to look crowded. You can always exit from the terminal window and open a new one, but there is a quicker and easier way to clear the contents displayed in the terminal: clearing the terminal.
To clear the terminal, type the command clear at the shell prompt. Thecommand then clears the terminal window.
Sometimes, you may accidentally open a program file or some other non-text file in a terminal window. After closing the file, you could find that the text you are typing does not match the output on the monitor.
In such cases, type reset to return the terminal window to its default values.