Extra terrestrial life
organisations such as SETI search for extra terrestrial life. They scan for signals in the sky for hundreds of thousands of computers and send out signals and receive messages.
The positives of ET life is the ET's can have technology they are willing to share. We can learn about them, and vice versa. Our knowledge of the universe could expand.
The negatives are that we may be inferior beings to them and they could attack us. They may not be intelligent being. They may bring in disease that could kill all mankind as we are not immune to their infections or whatever they carry. They may not understand us and we may not them.
An exoplanet is a planet orbiting a star which is not the sun.