Given the vastness of space, it may only be a matter of time before we make contact with intelligent extraterrestrials. But how might an alien civilization react to such a monumental meet-and-greet, and can we possibly know their intentions? Here's what we might expect.
Alien civilizations will most assuredly be like snowflakes: no two will be the same. Each will differ according to an array of factors, including their mode of existence, age, history, developmental stage, and level of technological development. That said, advanced civilizations may have a lot in common as they adapt to similar challenges; we all share the same Universe, after all.
We've obviously never interacted with an alien civilization, so we have virtually no data to go by. Predicting alien intentions is thus a very precarious prospect — but we do have ourselves to consider as a potential model, both in terms of our current situation and where we might be headed as a species in the future.