css layout

position: static, relative, absolute, fixed;
The position property allows you to specify the position of an element in three different ways.

the standard is default position, when we use ralative
When set to relative, an element's position is relative to its default position on the page.

don't move regardness of anything
When set to absolute, an element's position can be pinned to any part of the web page, but the element will still move out of view when the page is scrolled.

fixed is stronger than absolute. it won't move even user scroll.
When set to fixed, an element's position can be pinned to any part of the web page. The element will remain in view no matter what.

like x-y area, z represent depth. higher is go over it. -1 can be done.
The z-index of an element specifies how far back or how far forward an element appears on the page.

float: right;
The float property can move elements as far left or as far right as possible on a web page.

clear: left;

You can clear an element's left or right side (or both) using the clear property.