Histograms : they are different kind of bar cart where the values of data is distributed linearly or continuously. Where there is no gaps between the bars that present the different categories.
In given example below, the height of a building increasing as the months passed.. A histogram is used because time of construction of building is in continuous months. In bar chart the height of bar represent the size of particular category. However the histogram uses area to represent the category data in other term histogram use both x-axis and y-axis to represent the data on both scale.
whenever the six sigma method used to determine the value, histogram is the common tool to because its design in a way to help the user to process the information in defined way. If any changes are made into the program reflect clearly. Now all over the world six sigma business strategy going on it defined the business strategy. Therefore by using the histograms we can identify the problem and can make changes to solve it. It also help to determine the impact caused by any changes on the policies and procedure and six sigma can be used so that policies can easily used and altered. The main thing is to identify the issue and measure its complexity to solve the problem within the system.
Pareto chart : It is named after Wilfred Pareto. This chart contain both line and bars, where individual values in bar chart represent in decreasing order, and cumulative total present in line chart. Pareto chart is very important to give priority wise attention to the problem, those problem need attention first will get first because the taller bar on the graph shows the frequency therefore, which clearly states that which variable have the greatest cumulative effect on the system...