A lot has defined boundaries (or borders) which are documented somewhere, but the boundaries need not be shown on the land itself. Most lots are small enough to be mapped as if they are flat, in spite of the curvature of the Earth. A characteristic of the size of a lot is its area. The area is typically determined as if the land is flat and level, although the terrain of the lot may not be flat, i. e, the lot may be hilly. The contour surface area of the land is changeable and may be too complicated for determining a lot’s area.

Lots can come in various sizes and shapes. To be considered a single lot, the land described as the “lot” must be contiguous. Two separate parcels are considered two lots, not one. Often a lot is sized for a single house or other building. Many lots are rectangular in shape, although other shapes are possible as long as the boundaries are well-defined. Methods of determining or documenting the boundaries of lots include metes and bounds, quadrant method, and use of a plat diagram. Use of the metes and bounds method may be compared to drawing a polygon. Metes are points which are like the vertices (corners) of a polygon. Bounds are line segments between two adjacent metes. Bounds are usually straight lines, but can be curved as long as they are clearly defined.

When the boundaries of a lot are not indicated on the lot, a survey of the lot can be made to determine where the boundaries are according to the lot descriptions or plat diagrams. Formal surveys are done by qualified surveyors, who can make a diagram or map of the lot showing boundaries, dimensions, and the locations of any structures such as buildings, etc. Such surveys are also used to determine if there are any encroachments to the lot. Surveyors can sometimes place posts at the metes of a lot.