Stem and Leaf Plot

http://www.mrnussbaum.com/mathdrills/graphing/stemandleaf.htm

Stem and Leaf Plots are easy ways to display data by splitting each observation into two parts; the stem and the leaf. The stems are the digits on the left side and the leafs are the digits on the right side. Stem and leaf plots are useful when finding the mean or organizing the data in order of place value. The plot above shows students scores on a science test along the grading scale. The lowest score was 56 and the highest score was 97. 

Box Plot

https://onlinecourses.science.psu.edu/stat414/node/123

A Box Plot is a graph that displays five important numbers. The maximum value, the minimum value, upper quartile, lower quartile, and the median number are all displayed. These graphs are useful in displaying outliers and seeing how the data is distributed. In the box plot above, a very wide range of data points are displayed for peoples' IQ's. The data is fairly evenly distributed with almost 50% in the middle or the upper and lower quartile at about 100. The minimum is around 67 and the maximum is over 125. 

Histogram

http://www.netmba.com/statistics/histogram/

Histograms are frequency distribution graphs that show data points that fall into certain regions. Frequency is plotted on the y-axis while the groups are plotted on the x-axis, so each bar represent the number of times something occurred. In the histogram above, the exam scores of students are shown in intervals of 10. The highest frequency score was between 40-50%. 

Parallel Coordinate Graph

http://vis.lbl.gov/Vignettes/Drosophila/index.html

Parallel Coordinate Graphs are graphs that can be used when comparing two or more variables or data sets within a graph. These graphs can measure many things at once. In the parallel coordinate graph above, cells of nine different genes are shown. Each gene is represented by one of the nine parallel axis's. The level of expression is defined by a point on each axis. 

Triangular Plot

http://stackoverflow.com/questions/12520003/representing-ternary-plot-data-for-lookups

Triangular Plots are used to show the sum of the parts of three variables. The data is shown in an equilateral triangle in order to show the ratios of the three variables. In the graph above, soil composition can be determined by using the three variables. If the know the percent of sand, clay, and silt you can determine what substance you have. Also, you can use the percentages to determine what you need if you were to make something. All the percentages will add up to 100%. 

Windrose

http://www.originlab.com/index.aspx?go=Products/Origin/CustomizingGraphs&pid=1244

Windrose diagrams are used to show wind speed and wind direction over an extended period of time. The circle is usually divided into 16 slices, each representing a different direction. How far each arm extends out is dependent on the frequency that windspeed occurred. One the windrose above, the different colors represent different intervals of windspeed. In this windrose, actual windspeed data is compared to computer generated data. 

Climograph

http://www.colorado.edu/geography/extra/geogweb/bouldercreek-2/preview/page2.html

A Climograph is a representation of precipitation and temperature for a specific location over a length of time. Climographs are a quick and easy way to make a generalization about an areas climate. The climograph above is from Boulder, Colorado. Precipitation is represented by a bar graph and temperature is represented by a line graph. According to the graph, May was the wettest month and July was the hottest. 

Population Profile

http://www.census.gov/2010census/

Population Profiles are graphs that show data collected from a specific population based on certain variables such as age, race, income, and sex. Typically the chart will have two categories on the x-axis and one on the y-axis. These charts are often used to show population growth in Human Geography. This chart shows the population by sex and age in the District of Columbia in 2010. It can be determined that the largest group are females from the age of 20-30. 

Scatterplot

http://onlinestatbook.com/2/describing_bivariate_data/pearson.html

A Scatter Plot is a summary of bivariate data that is made up of individual points plotted on a graph. The points plotted show the relationship between two variables. Scatterplots can be used to form a trend line and show the association between the two variables. In the scatter plot above, the husbands' and wives' ages are plotted together. Since the points are relatively close together, there is a strong association between the two variables. 

Index Value Plot

http://waterwatch.usgs.gov/new/?m=real&w=plot&r=nm

Index Value Plots are plots that are useful in looking at changes over a period of years. These maps show variations in a particular situation. In this plot, the USGS is looking at streamflow in New Mexico. There is a standard line and the etchings in the line show variations from the normal as to whether it was a wet of dry year. 

Lorenz Curve

http://www.unc.edu/depts/econ/byrns_web/Economicae/Figures/Lorenz.htm

The Lorenz Curve, typically found in economics, is a graph that represents income distribution. The cumulative percentage of income is presented on the y-axis and the cumulative percent of households is presented on the x-axis. The black line is the line of perfect equality and the area of inequality is the pink shaded region. The Lorenz curve displays the imbalance of income. 

Bilateral Graph

http://www.theatlantic.com/international/archive/2010/10/china-and-international-rules-self-interested-or-malign/64747/

Bilateral Graphs are graphs that show more two or more sets of data on the same graph. The graph can be a bar graph, line graph, or another form of a graph. These graphs show both positive and negative values. The graph above shows the trade of clean energy products between the United States and China from 2006-2010. The blue bars represent indicate exports, the green lines indicate imports, and the red lines indicate trade deficits. 

Nominal Area Choropleth Map

http://www.eosnap.com/image-of-the-day/australia-september-6th-2008/

Nominal Area Choropleth Maps are maps that display areal data. These maps use different colors and patterns to distinguish certain regions. The information presented by these maps is nominal and qualitative data.  The map above is a map of Australia showing the different climate regions. This map only shows nominal data of what regions experience what type of climate. 

Unstandardized Choropleth Maps

https://www.ncjrs.gov/html/ojjdp/nrs_bulletin/nrs_2001_12_1/page23.html

Unstandardized Choropleth Maps are maps that take raw data and put them straight into the map. These maps can often times be misleading because they don't take into account outliers. The map above looks at arrests of Juveniles in the United States. The results could be skewed because of population differences from state to state. 

Standardized Choropleth Maps

http://www.statcan.gc.ca/pub/92f0138m/2008003/figures/5200001-eng.htm

Standardized Choropleth Maps are maps that display areally averaged data. Instead of just representing a total value, the information is standardized to a particular unit, usually area. They use constant methods for dividing the classes and they are normally very simple. The map above looks at the population in Canada that is under 14. Since the map is standardized, it is known that the data is accurate and set up into equal classes. 

Univariate Choropleth Maps

http://www.colocarto.com/custom-thematic-maps.html

Univariate Choropleth Maps are maps that only analyze one variable. These maps are useful when looking at one topic because they present the data in simple means. The map above measures the estimated median household income in 2008. The map uses simple classification methods, but uses less detail. As the level of income goes up, the color of red becomes deeper. 

Bivariate Choropleth Maps

http://www.personal.psu.edu/faculty/c/a/cab38/GEOG321/14_multivariate02/multivariate.html

Bivariate Choropleth Maps are choropleth maps that analyze two variables. The information is measured on a scale that allows the variables to be compared. The map above compares the people per square mile in 1990 with the percent change in population from 1990 to 2000 in the South Eastern United States. The different colors represent both of the variables. Looking at the two data sets together allows for conclusions to be made and generalizations to be drawn. 

Unclassed Choropleth Maps

http://candacesmaps.blogspot.com/2010/12/unclassed-choropleth-maps.html

Unclassed Choropleth Maps are maps that don't break the data up into classes, but rather just classify the data on a scale. These maps are useful when just a general overview of the data is needed. The map above is from the 2004 presidential election. This is a unclassed choropleth map because the key is a gradient and specific numbers don't have certain colors. The red shaded areas are areas that voted republican while the blue shaded areas are areas that voted democratic.  

Classed Choropleth Maps

http://my.ilstu.edu/~jrcarter/Geo204/Choro/Tom/

Classed Choropleth Maps divides the data into intervals and uses shading or coloring to present the data. There are several ways to separate the data, including equal groups, natural breaks, and quantiles. The map above shows the percent of people who are Hispanic or Latino living in each Florida county. The classes are set up equally to best represent the data. The darker green shades represent the counties with the largest Hispanic population.

Range Graded Proportional Circle Map

http://pubs.usgs.gov/fs/fs-004-03/

Range Graded Proportional Circle Maps are maps that illustrate data by groupings. These maps are nice because not only do they show data in the traditional proportional circles, but we see larger circles and larger data numbers. The images in the circles represent a range of data that each of the individual circles falls into. The map above shows river characteristics. The area of the circle measures channel width and the color of the circle approximates the color of the water.