Epithelial tissue is crucial for organizing the body's complex systems, creating order and separation to ensure proper function. It consists of different types of cells like squamous, cuboidal, and columnar, each serving specific functions based on their shape and layering.

Epithelial cells come in three distinct shapes: squamous, cuboidal, and columnar, each serving specific functions based on their structure. Squamous cells are flat for easy material transport, cuboidal cells are cubish for nutrient absorption, and columnar cells are tall for secretion production.

Epithelium can be classified based on the number of layers and the shape of its cells, with variations like simple squamous and stratified cuboidal tissues. The layering and cell shapes influence the tissue's function and regenerative capacity.