Extraterrestrial Life

While studying for my upcoming biology test, I was reading the book The Third Chimpanzee by Jared Diamond. I highly recommend it to anyone who is at all interested in human behaviors and/or evolution. Anyway, he discusses intelligent life on other planets and asks the following question: "What would happen if we found [extraterrestrial life], or it found us?

I reread it and then thought "o my gosh what WILL happen?" What will these creatures look like? Is it even fathomable that we will someday happen upon another life form from a distant planet? The odds are highly in favor of there being life out there somewhere, even if we never reach it and find out for sure. And according to Encyclopedia Britannica: "It is difficult to imagine life evolving on another planet without progressing towards intelligence."

Say that life on another planet has progressed towards intelligence enough, at least, to have some sort of radio transmitter (provided that they have all the same chemical elements on their planet as we do on ours and our capable of creating said radio transmitter); will our radio waves interact with each other? And if so, how are we going to communicate with them? We most likely don't have the same written or spoken language and probably don't look the same, so is it even worth trying to find out what other life is out there? As Jared Diamond so eloquently puts it, "we're unique and alone in a crowded universe. Thank God!"