Line-intersect sampling is a technique of unequal probability sampling for selecting the sampling units in the geographical area. A sample of lines is drawn in a study area and, whenever the sampling unit of interest is intersected by one or more lines, the characteristic of the unit which is under investigation is recorded. The process is illustrated in the figure which is drawn below. As an example, take an ecological habitat study in which the goal is to estimate the total quantity of the berries of a certain plant species in a particular region. A random sample of lines each of same length is selected and drawn on the map of the area. Field workers walk each of the lines and whenever line intersects a bush of the exact species, the number of berries on the bush is recorded.