Esri: Getting Started with GIS

raster

A data model that defines surfaces as an array of equally sized cells arranged in rows and columns. Each cell contains an attribute or measurement value. A raster's origin, cell size, and relative cell location are used to determine the location of the cells and raster on the earth.

vector

A data model that represents geographic features as points, polylines, and polygons. Attributes are associated with each vector feature, as opposed to a raster data model, which associates attributes with grid cells. Vector data uses pairs of geographic coordinates to determine the location of the features on the earth.

geographic coordinates

A measurement of a location on the earth's surface expressed in degrees of latitude and longitude.

mosaic dataset

A mosaic dataset is a collection of multiple rasters that acts as a catalog. The rasters are indexed so that you can easily query and search for the data.

feature

A representation of a real-world object on a GIS map.

GIS

Acronym for geographic information system. An integrated system of data, software, hardware, people and workflows used to answer questions, make decisions, and provide tools to create, share, and use geographic information.

metadata

Information that describes the content, quality, condition, origin, and other characteristics of data.

Points

Points are a single XY coordinate location. This image illustrates the points used to represent trees. Each point has a longitude and latitude location (also referred to as geographic coordinates) that defines the precise location of the feature on the earth. This image provides an example of the geographic coordinates for one of the tree points.

polygons

Polygons are defined using multiple locations that are connected and closed. This image illustrates a polygon used to represent the lake. Each location has a longitude and latitude (also referred to as geographic coordinates) that defines the precise location of the lake on the earth. This image provides an example of the geographic coordinates for one of the polygon locations.

polylines

Polylines are defined by two or more locations that are connected with lines. This image illustrates the polyline used to represent the river. Each location has a longitude and latitude (also referred to as geographic coordinates) that defines the precise location of the river on the earth. This image provides an example of the geographic coordinates for one of the polyline locations.

layer

References GIS data that represents real world features. The layer creates a symbol to represent the collection of these features. The features in a layer have the same theme, geometry, and set of attributes.

scale

Relationship between the size of a feature on a map and the actual size of that feature in the real world. Scales can be expressed as a ratio or an equivalence.

location query

Request for features based on the location and spatial relationship to other features. The three basic components of a location query are the layer containing features to select, the location relationship, and the layer containing the related features.

attribute query

Request for features based on values in the attribute table. The three basic components of an attribute query are the attribute field, operator, and attribute value.

raster data types:

TIFF, JPEG, mosaic dataset

data view

The data view is more commonly used when adding, editing, and analyzing the data. This view provides a table of contents that lists the map layers and can act as a legend.

layout view

The layout view is like a "page view," and it is often used before printing or sharing a map. In this view, you can display map elements like titles, legends, scale bars, and north arrows.

vector data types:

shapefile, CAD, geodatabase feature class