They select stars much like the Earth's sun and analyse signals they believe may be artificial. The SETI people assume that an extraterrestrial evolution of 4 billion years similar to ours, leads to a communication technology that we can pick up. Whilst this is a ver y strong assumption, on the other hand if we do not search, we will never know if anything is present. So it stands to reason that a certain fraction of the effort must be geared at doing the experiment. There can be very few people who have never gazed at the night sky and pondered on the mysteries of the Universe and our place within it.
Astronomy tells a fascinating story.
It is a tale made all the more enthralling by the ease with which anyone can participate in astronomical observation. The very word astronomy, conjures up wonderful images in your mind of distant galaxies, exploding stars, comets, meteors, telescopes and yes life elsewhere in the Universe. It may also bring to mind your very first look through a telescope or binoculars. Whatever comes to mind, the subject of astronomy has captured the hearts and minds of virtually every person on the planet at some time or another. So, if you are new to astronomy, take your time in learning your way around the night sky.