A
graph is a visual display of some
data. In most cases, the
data exists in the form of a table. In many cases, the table itself is displayed. However, the same
data, displayed as a
graph, often creates more impact. A
graph also makes it easier to understand, or interpret, the
data that is being presented. When you interpret a
graph, you can compare values and spot trends in the
data. There are many different types of
graphs.
A
bar graph is shown on the screen. A
bar graph is useful for comparing values over time. A
bar graph consists of a series of rectangles or bars.
A
bar graph is also useful for comparing values between groups of items. Such a
graph is called a
double bar graph.
A
bar graph in which there is no gap between the bars is called a
histogram. A
histogram is useful for showing the distribution of data over intervals.
A
pie graph or a
pie chart is useful for showing the proportion of each data value to the whole.
A
line graph usually shows a visual comparison between
two quantities using a series of line segments. The line segments are
joined end-to-end. The
line graph, thus, allows us to observe trends easily. This is a major advantage of the
line graph.