Body Language

Communication is of two types, verbal and non verbal. Body language is the non verbal communication which just can't be fake. If you know to read body language you can easily figure out what's going on someone's mind. Anyone can pretend while speaking but the body language speaks only truth.

Basic Body language signals:

Eyes: Eyes communicate more than any other part.

Liars will never look at your eyes while talking or will make more eye contact than usual in an attempt to make you believe they are telling you the truth.
While listening to you if someone is looking away this means the person is thinking about something else.
Twinkling of eyes means Amused.
Wide open eye is the sign of Fear.
Eyebrows Down and Together (toward nose), Eyes Staring conveys anger.
Eyebrows Raised in the Middle means sadness.

Legs:

A fast tapping, shifting of weight, or movement of the foot will most often mean that the person is excited, nervous, scared, or intimidated.
Feet Back, Behind Knees shows Interest
Feet Out, on Heels symbolizes Disinterest, Bored
Legs Crossed given an impression that the person is not open to conversation.

Arms:

People with crossed arms are closing themselves to social influence.
If someone rests their arms behind their neck, they are open to what is being discussed and interested in listening more.
If the hands are in their pockets, then they are more relaxed and are more likely to be attracted to you.

Gestures:

If someone brushes their hair back with their fingers, this may be preening.
Raised eyebrows means they disagree with you.
If the person wears glasses, and is constantly pushing them up onto their nose again, with a slight frown, that may also indicate they disagree with what you are saying.
If someone is playing with their hair, they are feeling self-conscious, flirting, or possibly uncomfortable.
If someone is biting their lip, they are anticipating something.

In groups there is typically one person speaking at a time but many more can be showing their responses via body language. Some researchers put the level of nonverbal communication as high as 80 percent of all communication. So next time when you are communicating with someone, try to read the gestures and also try to improve your body language so that others don't interpret you wrong.

(Sources: positive-way.com, speech-time.com)