The technique of ‘reading’ people is used frequently. For example, the idea of mirroring body language to put people at ease is commonly used in interviews. Mirroring the body language of someone else indicates that they are understood.

Body language signals may have a goal other than communication. Both people would keep this in mind. Observers limit the weight they place on non-verbal cues. Signalers clarify their signals to indicate the biological origin of their actions.

* One of the most basic and powerful body-language signals is when a person crosses his or her arms across the chest. This can indicate that a person is putting up an unconscious barrier between themselves and others. It can also indicate that the person’s arms are cold which would be clarified by rubbing the arms or huddling. When the overall situation is amicable, it can mean that a person is thinking deeply about what is being discussed. But in a serious or confrontational situation, it can mean that a person is expressing opposition. This is especially so if the person is leaning away from the speaker. A harsh or blank facial expression often indicates outright hostility.

* Consistent eye contact can indicate that a person is thinking positively of what the speaker is saying. It can also mean that the other person doesn’t trust the speaker enough to “take his eyes off” the speaker. Lack of eye contact can indicate negativity. On the other hand, individuals with anxiety disorders are often unable to make eye contact without discomfort. Eye contact is often a secondary and misleading gesture because we are taught from an early age to make eye contact when speaking. If a person is looking at you but is making the arms-across-chest signal, the eye contact could be indicative that something is bothering the person, and that he wants to talk about it. Or if while making direct eye contact a person is fiddling with something, even while directly looking at you, it could indicate the attention is elsewhere. Also there are three standard areas that a person will look which represent different states of being.
- if the person looks from one eye to the other then to the forehead it is a sign that they are taking an authoritative position;
- if they move from one eye to the other then to the nose, that signals that they are engaging in what they consider to be a “level conversation” with neither party holding superiority;
- the last case is from one eye to the other and then down to the lips. This is a strong indication of romantic feelings.

* Disbelief is often indicated by averted gaze, or by touching the ear or scratching the chin. When a person is not being convinced by what someone is saying, the attention invariably wanders, and the eyes will stare away for an extended period.

* Boredom is indicated by the head tilting to one side, or by the eyes looking straight at the speaker but becoming slightly unfocused. A head tilt may also indicate a sore neck or Amblyopia, and unfocused eyes may indicate ocular problems in the listener.

* Interest can be indicated through posture or extended eye contact.

* Deceit or the act of withholding information can sometimes be indicated by touching the face during conversation. Excessive blinking is a well-known indicator of someone who is lying.

It should be noted that some people (e.g., people with certain disabilities, or those on the autistic spectrum) use and understand body language differently, or not at all. Interpreting their gestures and facial expressions (or lack thereof) in the context of normal body language usually leads to misunderstandings and misinterpretations (especially if body language is given priority over spoken language). It should also be stated that people from different cultures can interpret body language in different ways.