Do you know photographic mosaic?

Can you identify the technique used to form this image? It is called 'photographic mosaic.'

Let me refresh your memory. I was studying 10th standard when I was taught this method of art. I was given an assignment of drawing the map Japan in size of 6 by 6. The idea used was like the photographic mosaic where a picture made of smaller pictures.

You might have seen the pictures of Mona Lisa, made by using the technique of photomosaic.

We draw several smaller rectangular sections of an image with smaller pictures or photographs of an appropriate average color. When viewed from afar, a primary image is visible, but when examined closely, the hundreds or thousands of smaller images acting as pixels are revealed.

Thank you The Free Dictionary!