Fill

Reference

Mode

Edit Mode

Menu

Face ‣ Fill

Hotkey

Alt-F

The Fill option will create triangular faces from any group of selected edges or vertices, as long as they form one or more complete perimeters.

Beauty

Arrange the new triangles nicely.

Filled using fill.

Note, unlike creating n-gons, Fill supports holes.

A closed perimeter of edges with holes.

Filled using fill.