Here's a breakdown:

* Epithelial tissue is made up of tightly packed cells that form sheets covering surfaces and lining cavities. There are many types of epithelial tissue, but one key characteristic is the shape of the cells.

* Squamous epithelial tissue is specifically characterized by its flat, scale-like cells.

Examples of squamous epithelium include:

* Simple squamous epithelium: This type forms a single layer of flat cells and is found in areas where diffusion or filtration occurs, like the lining of blood vessels (endothelium) and the air sacs in the lungs (alveoli).

* Stratified squamous epithelium: This type consists of multiple layers of cells, with the superficial cells being flat. It is found in areas subject to abrasion, like the skin and the lining of the mouth.

Other tissue types also have cells with varying shapes, but squamous cells are most commonly found in epithelial tissue.