I don’t know much about bricks, except that they are fired clay. But I do like to see them when they are used decoratively. The way they are laid is called the ‘bond’ where it depends whether they are laid horizontally across the surface of the wall, or with the short end showing on the face of the wall and the length turned 90° so that the brick is across into the layer behind or allows the wall to turn the corner at the edge of the building.
As you can see from this photo, different coloured bricks are often used to make patterns and shapes in the brickwork or are used to frame tiled areas of text stating when the building was built.
I also know that brick sizes changed over time. That they were smaller in the past and hand made. Then molds were made and the brick sizes became standardised. I don’t know all the history of that sorry.