Answer:
These are arbitrary names for parcels of land, and the names of the items and their legality will depend upon the jurisdiction.
2nd Answer:
Townships are 6-mile by 6-mile 'squares' of land that are used to divide land into legally-describable portions. Most land west of the Mississippi River is divided by Townships, but east of the Mississippi, the use of Townships is spotty and variable.
The 36 Sections within a Township measure 1 mile square, more or less, and are numbered boustrephedonically - that is, 1 through 6, right to left, 7 through 12 left to right, 13 through 18 right to left, and so on.
Townships are located by Range, that is, the number of Townships from some arbitrary and widely accepted starting monument east or west. Townships are also numbered by Tiers to the north or south. Tiers are often mistakenly called townships, too, but you can see the confusion that could result. As an example, a particular Section where I work is Section 33, Tier 15 North, Range 45 East from Willamette Meridian.
Each Section is further divided by quarter sections, government lots, and tracts.