Table (landform) from almost all directions, terminating in cliffs. Table (landform) A table or tableland is a butte, flank of a mountain, or mountain, that has a flat top. This landform has numerous names in addition to "table", including: The term "flat" is relative when speaking of tables, and often the naming or identification of a table (or table hill or mountain) is based on the appearance of the terrain feature from a distance or from below it. An example is Mesa Verde, Colorado, where the "flat top" of the mountain is both rolling terrain and cut by numerous deep canyons and
Optical flat is also needed, on which the test can be performed, preventing both the flat and the test-piece from sagging under their combined weight, Often, a precision-ground surface plate is used as a work surface, providing a steady table-top for testing upon. To provide an even flatter surface, sometimes the test may be performed on top of another optical flat, with the test surface sandwiched in the middle. Absolute flatness is the flatness of an object when measured against an absolute scale, in which the reference flat (standard) is completely free of irregularities. The flatness of any optical flat is relative