"Everything in existence is energy and gives off waves. Empaths are merely magnets for those energy waves, some feeling small crests while others live bombarded with tidal waves." -- from Can You Spot the Empath?
Empaths have the ability to scan another’s energy for thoughts, feelings and possibly for past, present, and future life occurrences. Most empaths are unaware of how this really works, and have accepted that they are sensitive to other people’s energy.
Being an Empath ~ Feeling others emotions and taking them on as your own: This is a huge one for empaths. To some they will feel emotions of those near by and with others they will feel emotions from those a vast distance away, or both. The more adept empath will know if someone is having bad thoughts about them, even from great distance...
Do you feel overwhelmed when going to a mall, a sporting event, or Wal-Mart? Somewhere where there might be a lot of people? You want to go, but when you get there you feel anxious, unsettled, or “very off” but you don’t know why? You might be an Empath... http://www.keystothespiritworld.com/2013/04/6-signs-you-are-empath.html