The Third Eye.
The third eye is a chakra that is responsible for what we call "second sight". Intuitive perception. Empathy is a property of the heart Chakra, but it is by the third eye that people see ghosts, auras and other usually non-visible phenomena. The perceptions of the third eye are not limited by time or space. The Third Eye sees energy patterns, and it is not limited by distance. So focusing on the Third Eye, you can see things that are happening on the other side of the world. You can see things that happened in the past. You may see potential events that happen in the future. I don't recommend spending a lot of time doing that, as the point of power is always in the here and now. It's actually much simpler just to use it to observe your own energy patterns, to look inside of yourself, and see how you are doing.
Some reptiles have an "eye" on the top of their heads, that sees infrared and heat. Our third eye evolved from this, but instead of being on the surface of our skull it is deep inside, in the very centre of your head at the pineal gland. However, when most people think of the third eye, they think of it being in the centre of the forehead or between the brows. In fact the third eye is an area that goes from the tip of your nose to the top of your forehead and deep inside your brain. It has many components, including an area near the back of your sinuses that responds to emotional energy.
I want to clear up a misconception that may people have, about how psychic vision works. Most people imagine that when a psychic "sees" something she does it with her regular eyes: not so, the "second sight" is most often seen in the mind's eye. As an imaginary or internal vision. Usually it is the inward vision that shows the insights. When you think of the inward sight, an easy way to imagine it, is that your forehead has a projector lens that projects holograms onto the back of your head.
When you close your eyes and roll them towards your forehead, in a dark room, do you see a light? If the third eye is well opened, you should see a golden glow that might appear donut-shaped. It may be an irregular glow, it may be so large that you can only see the bottom of the donut ring, or the donut may have a tiny light in the centre.
At some point, you may get a blue light appearing. It's very tiny. Muktananda referred to this as the "blue pearl of wisdom". If this light shows up, ask it to stay and guide you, and be your guide for the rest of your life. And if you ask it, then it will. And you can ask it anything because it knows everything.
To look at your own energy, imagine you are standing behind yourself and look at yourself from the back. You may dismiss it as "only imagination." Yet, imagination is power. Einstein said "imagination is more important than knowledge." He ought to know, he imagined what it would be like, to be a photon and came up with the theory of relativity.
Sometimes in a light trance or in dim light the physical and inner visions overlap, and you may see spirits or auras with your physical eyes. That is why ghosts are most often seen at twilight. The third eye is also more active in the peripheral vision, and that is why you sometimes may see things out of the corner of your eye, that vanish when you look straight at them. To see these things, keep your head and eyes still and turn your inner eye to focus on the anomaly.
Kung Fu Masters and speed readers both make use of a type of "soft focus" that expands the abilities of the peripheral vision. To try it, focus on a single object very intently, then without moving your eyeballs, let your focus soften so you can see the other objects around the one you are focusing on with equal clarity. Keep your eyes forward and contemplate what you can see in your peripheral vision. Try it now, with your computer screen. Gradually soften your focus to take in your monitor, then the area around your computer, while still seeing these words clearly
The best shortcut is to simply ask your Divine Self/ the Divine aspect of your own unconscious mind, what something looks like. So much faster, easier and than more accurate than trying to see for yourself. The mental images appear immediately, plus they often come with a sense of understanding the meaning of what you are shown. Cultivating this technique is easier and more useful than all the stuff around third eye opening, and will lead to that anyway over time.