A graph is a visual display of numeric values. A graph is a picture. Graphs make numbers and number comparisons more understandable. Graphs summarize data, show trends, and display patterns. Graphs make it quick and easy to interpret a large amount of data.
The most common graph is a bar graph or column chart. Bar graphs display information with shaded columns. In a bar graph the highest column demonstrates the highest number or the most quantity. A bar graph would be used to show how many auto parts were sold each month for the past 12 months.This bar graph would show management instantly what months were the most productive. Management would know at a glance which months had the most business or most parts sold. A bar graph could also be used to show how many students in a class had blue eyes, brown eyes, or hazel eyes.
Line graphs display information as points connected by a line. Line charts are used to identify trends. The most common line chart is used to display a stocks performance in the stock market. The line chart allows an individual to see the highest and lowest value of a stock over time. The line chart allows an individual to see if the value of a specific stock is rising in value or decreasing in value. If a stock has been flat and starts to rise, it signifies that it is time to buy. If a stock has been rising steadily and starts to decline, it signals that it is time to sell. Another well used line chart is a baby's growth chart. The pediatrician compares a baby's height and weight to the growth chart to determine if the baby is growing at age level, is smaller than the average baby at that age, or is bigger than the average baby at that age.
A pie or circle graph is used to show contributions or slices of a whole. Five or six slices are the ideal data size for a pie graph. A pie graph is commonly used to show where the money is spent to help a family stay within a budget. One pie slice shows the amount of money spent on the house payment, a second slice shows the amount spent on utilities, the third slice the amount of money spent on car expenses, the next slice the amount spent on food, another slice shows the amount spent on clothing, and the last slice shows the money spent on entertainment. The pie slices or budget can be adjusted if one slice seems to large in comparison to the others. Another common use of a pie or circle graph is to show the types of injuries in a work place. It is easy to see if the number of computer injuries is bigger than the number of falls, bee stings, or auto accidents.
Microsoft Excel is a common computer business application spreadsheet. A spreadsheet is a row and column representation of numbers. Excel is so popular because once the data has been entered into the spreadsheet, a visual representation of the data can be displayed with just click of the mouse. Excel can visually display the spreadsheet data in bar, line, or pie graphs. The visual display can be changed from one to the other easily to determine what graph shows the best picture.