3-d videos in YouTube

This is a way by which you can create and watch 3-d videos. There was a time when 3-d videos needed special kind of projectors and spectacles which could be set up only in Cinema Halls.
But Nowadays 3d videos can be seen from even your home.

I first saw this stuff in YouTube but few people have actually understood it and the ones who have are awestruck about seeing something they thought was impossible.
I will post this blog in the form of questions.

1.What is 3-d video?
---It is actually a video in which the particles appears to project outside form the screen which gives us a sense of reality.

2.How to watch it?
--- The video is not actually to be seen with your naked eyes. You need a special kind of spectacles which can be made even at your home. All you need to do is create a frame with cardboard and fix a blue "glass paper"(it is actually a coloured plastic sheet which is transparent) as the right glass and a red glass paper as the left glass.
The video appears 3-d when you watch it using this spectacles.

3.How does this work?
--- When you watch the video with your naked eyes you can see that there are actually two images of a single particle. One in red and the other in blue, both separated by a small distance. For example if it is a man, there is a real image of him in blue and another in red.
When your right eye sees it through the blue glass it can see only the red image as the blue image gets mixed up in the color of glass. In same way the left eye can see only the blue image as red image gets lost too. So each of your eye sees two different images which is actually separated by a small distance.

But when you actually view an object both your eyes sees the same object and your mind forms a combined image of both of those images.

But in this case as the two images are different the combined image formed appears to be projected from screen.