Isopleth Map

Source Urhttp://www.lewishistoricalsociety.com/wiki/tiki-read_article.php?articleId=65

An isopleth map uses contour lines to display information that is collected over an area rather than a particular point.  This map displays the sea level pressure over an area.

Index Value Plot

Source Url: http://www.securitystockwatch.com/InvestmentGuides/Water_Stocks.html

An index value plot shows data in a linear model in which outliers and influential points can be observed.  The attached map shows the value of different indices over time.  An index value plot is a valuable tool used to compare data.

Continuously Graded Proportional Circle Map

Source Url: http://geographyfieldwork.com/DataPresentationMappingTechniques.htm

A continuously graded proportional circle map uses data represented by circles whose size relates to a specific variable.  The size of the circle is not necessarily determined by the area of the region.

Isoline Map

Source Url: http://giscommons.org/?page_id=18

An isoline map uses contour lines to represent measured data.

DEM

Source Url: http://tahoe.usgs.gov/GIS.html

A digital elevation model (DEM) is a representation of a terrain's surface.  DEM's may be three dimensional or digital models.  They are created using elevation information.  The attached image is a digital model of the Tahoe region.

Parallel Coordinate Graph

Source Url: http://www.stat.columbia.edu/~cook/movabletype/archives/2007/10/parallel_coordi.html

A parallel coordinate graph is a visual representation of the relationship between various sets of data to include overlap.

DOQQ

Source Url: http://www.crwr.utexas.edu/gis/gishydro00/Class/trmproj/Donnelly/termproject.htm

A Digital Orthophoto Quarter-Quadrangle (DOQQ) image is a scale representation of a topographical map area.  It is created using aerial photography.