Applications of GIS

ASCII files*

"American Standard Code for Information Interchange". The de facto standard for the format of text files in computers and on the internet that assigns an 8-bit binary number to each alphanumeric or special character. ASCII defines 256 possible characters.

SPC

"State Plane Coordinates", "Standard Pixel Count" or "Statistical Process Control" ***

CAD

(Computer-Aided Design). A computer-based system for the design, drafting, and display of graphical information. Such systems are mostly commonly used to support engineering, planning, and illustrating activities.

DRG*

(Digital Raster Graphic) A raster image of a scanned USGS standard series topographic map, usually including the original border information, referred to as the map collar, map surround, or marginalia. Source maps are georeferenced to the surface of the earth, fit to the universal transverse Mercator (UTM) projection, and scanned at a minimum resolution of 250 dpi. The accuracy and datum of a DRG matches the accuracy and datum of the source map.

FTP

(File Transfer Protocol) A protocol that allows the transmission of files between computers over a network.

GIS

(Geographic Information System) An integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes. A GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed.

GPS

(Global Positioning System) A system of radio-emitting and -receiving satellites used for determining positions on the earth. The orbiting satellites transmit signals that allow a GPS receiver anywhere on earth to calculate its own location through trilateration. Developed and operated by the U.S. Department of Defense, the system is used in navigation, mapping, surveying, and other applications in which precise positioning is necessary.

GUI

(Graphical User Interface) A software display of program options that allows a user to choose commands by pointing to icons, dialog boxes, and lists of menu items on the screen, typically using a mouse. This contrasts with a command line interface in which control is accomplished via the exchange of strings of text.

JPEG*

(Joint Photographic Experts Group) A lossy image compression format commonly used on the Internet. JPEG is well-suited for photographs or images that have graduated colors.

Microsoft SQL Server

(Structured Query Language) A syntax for retrieving and manipulating data from a relational database from a server.

TIFF

(Tagged Image File Format) is a file format for storing images.

.shp file*

- a vector data storage format (shapefile) for storing the location, shape, and attributes of geographic features. - stored in a set of related files and contains one feature class.

image map

...

arc*

1. On a map, a shape defined by a connected series of unique x,y coordinate pairs. An arc may be straight or curved. 2. a coverage feature class that represents lines and polygon boundaries. One line feature can contain many arcs. Arcs are topologically linked to nodes and to polygons. Their attributes are stored in an arc attribute table (AAT). Nodes indicate the endpoints and intersections of arcs; they do not exist as independent features. Together, the from-node and the to-node define the direction of the arc

file

A collection of uniquely named information stored on a drive, disk, or tape. A file generally resides within a directory.

field

A column in a table that stores the values for a single attribute. The place in a database record, or in a GUI, where data can be entered. A synonym for surface.

document

A component of an ArcView 3.x project. Each document type (view, table, chart, layout, script) has its own window and interface.

computer file

A computer file...

Oracle

A database company that produces a relational database management system (also called Oracle), which allows data and other objects to be stored in tables. Oracle provides client/server access to data and uses indexes, sequences, and other database objects to facilitate rapid data creation, editing, and access. ESRI uses Oracle's RDBMS to store vector and raster data for use by ArcSDE.

attribute table

A database or tabular file containing information about a set of geographic features, usually arranged so that each row represents a feature and each column represents one feature attribute. In raster datasets, each row of an attribute table corresponds to a certain zone of cells having the same value. In a GIS, attribute tables are often joined or related to spatial data layers, and the attribute values they contain can be used to find, query, and symbolize features or raster cells.

Geographic Database

A database that contains geographic information that lists properties about the geographic area.

Microsoft Access

A database tool for gathering and understanding information. It is also the underlying database used by Oracle enterprise. ArcGIS has the ability to use tables from a Microsoft Access database in ArcMap.

Interface

A device or program enabling a user to communicate with a computer.

full extent

A feature in ArcGIS that shows the entire layer of a certain database.

String

A field type: A set of coordinates that defines a group of linked line segments.

file type

A file with an unique extension written for a certain type of program. ***

raster format

A format for storing and displaying GIS spatial data that is store as cells or pixels. Since raster does not use a continuous coordinate system, it is less accurate at georeferencing than a raster data.

vector format

A format for storing and displaying GIS spatial data that is store as points, lines or areas to create a map object. By using a nearly continuous coordinate system, vector data can be more accurately georeferenced than a raster data.

personal geodatabase*

A geodatabase that stores data in Microsoft Access. A personal geodatabase can be read simultaneously by several users, but only one user at a time can edit the same data.

point

A geometric element defined by a pair of x,y coordinates.

menu

A list of available commands or operations displayed on a computer screen from which a user can make a selection.

thematic mapping

A map designed to convey information about a single topic or theme, such as population density or geology.

data frame/layout frame

A map element that defines a geogrpahic extent, a page extent, a coordinate system, and other display properties for one or more layers in ArcMap. A dataset can be represented in one or more data frames. In data view, only one data frame is displayed at a time; in layout view, all a map's data frames are displayed at the same time. Many cartography texts use the term "map body" to refer to what ESRI calls a data frame.

line feature

A map feature that has length but not area at a given scale, such as a river on a world map or a street on a city map.

point feature

A map feature that has neither length nor area at a given scale, such as a city on a world map or a building on a city map. In ArcGIS software, a digital map feature that represents a place or thing that has neither length nor area at a given scale.

graduated symbol map

A map with symbols that change in size according to the value of the attribute they represent. For example, denser populations might be represented by larger dots, or larger rivers by thicker lines. http://downloads.esri.com/support/gisDictionary/images/graduated-symbol-map.gif

geographic coordinates*

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

marker palette

A palette that lets you customize the markers that represent real-world objects on a map.

end nodes*

A point at which lines or pathways intersect or branch. Th end node is the first or last connecting point.

dot density map

A quantitative, thematic map on which dots of the same size are randomly placed in proportion to a numeric attribute associated with an area. Dot density maps convey the intensity of an attribute.

palette

A range of colors or shapes available to the user.

color ramp

A range of colors used to show ranking or order among classes on a map

CAD feature class

A read-only member of a CAD feature dataset, comprised of one of the following: polylines, points, polygons, multipatch, or annotation. The feature attribute table of a CAD feature class is a virtual table comprised of select CAD graphic properties and any existing field attributes values.

hyperlink

A reference (link) from one point in an electronic document to another document or another location in the same document (the target). Activating the link, usually by clicking it with the mouse, causes the browser to display the target of the link.

coordinate system

A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions. The Cartesian coordinate system and the geographic coordinate system used on the earth's surface are common examples of coordinate systems.

map feature

A representation of a real-world objects on a map.

attribute query*

A request for records of features in a table based on their attribute values

class*

A set of entities grouped together on the basis of shared attribute values. Pixels in a raster file that represent the same condition a template for a type of object in an object-oriented programming language. A class is used to create objects that share the same structure and behavior

coordinate*

A set of values represented by the letters x, y, and optionally z or m (measure), that define a position within a spatial reference. Coordinates are used to represent locations in space relative to other locations.

Difference between .shp and .lyr file?

A shapefile is a geographic map, containing all spatial information needed to display the data. A layer file is comprised of the symbology of the shapefile.

raster cell

A single cell of a raster file that contains attribute values and location coordinates about the cell.

client - server

A software system with a central processor (server) that accepts requests from one or more user applications, comptuers, or devices (clients). Although client/server architecture can exist on one computer, it is more relevant to (and is typically thought of as relating to) network systems that distribute applications over computers in different locations.

Geographic Feature

A specific detail or an object on a map.

ArcGIS*

A suite consisting of a group of geographic information system (GIS) software products produced by ESRI. It is a system for working with maps and geographic information. It is used for: creating and using maps; compiling geogrpahic data; analyzing mapped information; sharing and discovering geographic information; ;using maps and geogrpahic information in a range of applications; and managing geographic information in a database.

stateplane coordinates

A system of X,Y coordinates defined by the U.S. Geological Survey for each state. Locations are based on the distance from an origin within each state.

pen palette

A tool that allows the user to select a range of pen thickness and colors to customize the display.

query builder, query button

A tool that allows the user to select features or records from a database. A query is often written as a statement or logical expression.

auto-label*

A tool that automatically labels a certain layer based on a selected field (usually NAME)

arithmetic function

A type of methematical function that performs a calculation on the values of cells in an input raster. There are six arithmetic functions in ArcGIS Spatial Analyst: Abs, Int, Float, Round up (Ceil), Round down (Floor) and Negate

digital orthophoto

Aerial photography geometrically corrected for camera tilt and ground relief.

georeferencing

Aligning geographic data to known coordinate system so it can be viewed, queried, and analyzed with other geographic data. Georeferencing may involve shifting, rotating, scaling, skewing, and in some cases warping, rubber sheeting, or orthorectifying the data.

legend editor

An ArcGIS tool that lets the user customize the legend that will be displayed in the document.

orthophoto maps

An aerial photograph from which distortions owing to camera tilt and ground relief have been removed. An orthophotograph has the same scale throughout and can be used as a map. http://downloads.esri.com/support/gisDictionary/images/orthophotograph.gif

foreign key*

An attribute or set of attributes in one table that match the primary key attributes in another table. Foreign keys and primary keys are used to join tables in a database.

bitmap*

An image format in which one or more bits represent each pixel on the screen. The number of bits per pixel determines the shades of gray or number of colors that a bitmap can represent

graphics

An image produced by and stored in a computer as data for display.

coordinate pairs

An x and y used to represent a location.

dBASE file (recheck this)

Another word for database file.

geographic information system*

Any system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data.

Operators

Arithmetic - *, /, -, + Boolean - True or False Relational - ==, >, <, <>, >=, <=

types of fields

Character, integer, decimal, single, double, and string

feature attribute table*

Contains description about the feature in an attribute table listed as records with one or multiple fields. ***

document windows

Different windows containing different document types and interface. ***

Relational operators: ==, <,>,<>,>=,<=

Evaluate specific relational conditions. If the condition is TRUE, the output is assigned 1; FALSE, output is assigned 0.

linear feature

Features on a map that is represented with a line (a line with length but no width).

attribute table: field and records

Field are the columns. Records are the rows.

feature class*

In ArcGIS, a collection of geographic features with the same geometry type (such as point, line, or polygon), the same attributes, and the same spatial reference. Feature classes can be stored in geodatabaases, shapefiles, coverages, or other data formats. Feature classes allow homogeneous features to be grouped into a single unit for data storage purposes. For example, highways, primary roads, and secondary roads can be grouped into a line features class named "roads." In a geodatabase, feature classes can also store annotation and dimensions.

layer

In ArcGIS, a reference to a data source, such as a shapefile, coverage, geodatabase feature class, or raster, that defines how the data should be symbolized on a map. Layers can also define additional properties, such as which features from the data source are included. Layers can be stored in map documents (.mxd) or saved individually as layer files (.lyr). Layers are conceptually similar to themes in ArcView 3.x.

ID tool

In ArcGIS, a tool that, when applied to a feature (by clicking it), opens a window showing that feature's attributes.

Identify

In ArcGIS, a tool that, when applied to a feature (by clicking it), opens a window showing that feature's attributes.

label

In ArcGIS, descriptive text, usually based on one or more feature attributes. Labels are placed dynamically on or near features based on user-defined rules and in response to changes in the map display. Labels cannot be individually selected and modified by the user. Label placement rules and display properties (such as font size and color) are defined for an entire layer.

layout view

In ArcMap and ArcReader, a view that shows the virtual page upon which geographic data and map elements, such as titles, legends, and scale bars, are placed and arranged for printing.

map document

In ArcMap, the file that contains one map, its layout, and its associated layers, tables, charts, and reports. Map documents can be printed or embedded in other documents. Map document files have a .mxd extension.

destination table

In ArcView 3.x, one of the two tables involved in a join operation. The destination table must be the active table; the attributes of the source (inactive) table are appended to it.

node*

In a geodatabase, the point representing the beginning or ending point of an edge, topologically linked to all the edges that meet there. In a coverage, the beginning or ending point of an arc, topologically linked to all the arcs that meet there.

format

In computing, the structure and organization of digital information.

Geographic Data

Information describing the location and attributes of things, including their shapes and representation. Geographic data is the composite of spatial data and attribute data.

Joining and Linking Tables*

Joining: Appending the fields of one table to those of another through an attribute or field common to both tables. A join is usually used to attach more attributes to the attribute table of geographic layers. One-to-many- only link. one-to-one-link or join many-to-many-link or join

latitude/longitude

Latitude: angular distance, usually measured in degrees northn or south of the equator. Lines of latitude are also referred to as parallels. Longitude: angular distance, usually expressed in degrees, minutes, and seconds, of the location of a point on the earth's surface east or west of an arbitrarily defined meridian (usually the Greenwich prime meridian). All lines of longitude are great circles that intersect the equator and pass through the North and South Poles.

one-to-many/MANY-TO-MANY relationships

Many-to-one: an association between two linked or joined tables in which many records in the first table may correspond to a single record in the second table. Many-to-many: an association between two linked or joined tables in which one record in the first table may correspond to many records in the second table, and vice versa.

desktop GIS

Mapping software that is installed onto and runs on a personal computer and allows users to display, query, update and analyze data about geographic locations and the information linked to those locations.

location query

Mathematically select objects in a certain location.

attributes*

Nonspatial information about a geogrpahic feature in a GIS, usually stored in a table and linked to the feature by a unique identifier. For example, attributes of a river might include its name, length, and sediment load at a gauging station.

polygon

On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique. http://downloads.esri.com/support/gisDictionary/images/polygon.gif In ArcGIS software, a shape defined by one or more rings, where a ring is a path that starts and ends at the same point. If a polygon has more than one ring, the rings may be separate from one another or they may nest inside one another, but they may not overlap.

line

On a map, a shape defined by a connected series of unique x, y coordinate pairs. A line may be straight or curved. http://downloads.esri.com/support/gisDictionary/images/line.gif

character data types

One of the field types: a letter, digit, or special graphic symbol treated as a single unit of data and usually stored as one byte.

area feature

One of the three types of features: point, line, and area. The area feature is a 2D plane produced by a polygon of a certain shape.

database

One or more structured sets of persistent data, managed and stored as a unit and generally associated with software to update and query the data. A simple database might be a single file with many records, each of which references the same set of fields. A GIS database includes data about the spatial locations and shapes of geographic features recorded as points, lines, areas, pixels, grid cells, or TINs, as well as their attributes.

relational database management system

Software systems that store data in such a way that tables can be joined together by linking on a common items of data, termed a key.

file name extensions

The abbreviation following the final period in a file name that indicates the file's format, such as .shp, .zip, or .tif. File name extensions are usually one to four letters long.

labeling features

The ability to label certain layers and display it on arcGIS based on a selected field (usually NAME).

raster resolution

The amount of detail that is shown for that particular raster image. The smaller and more frequent the raster cells, the higher the resolution and vice versa. ***

layout

The arrangements of elements on a map, possibly including a title, legend, north arrow, scale bar, and geographic data. In ArcGIS, a presentation document incorporating maps, charts, tables, text, and images.

data type (recheck this)

The attribute of a variable, field, or column in a table that determines the kind of data it can store. Common data types include character, integer, decimal, single, double, and string.

active data frame*

The data frame currently being worked on - for example, the data frame to which layers are being added. The active data frame is highlighted on the map, and its name is shown in bold text in the table of contents.

legend

The description of the types of features included in a map, usually display in the map layout. Legends often use graphics of symbols or examples of features from the map with a written description of what each symbol or graphic represents http://downloads.esri.com/support/gisDictionary/images/legend.gif

active layer

The layer that is currently active.

extent

The minimum bounding rectangle (xmin, ymin and xmax, ymax) defined by coordinate pairs of a data source. All coordinates for the data source fall within this boundary.

file name

The name that distinguishes a file from all other files in a particular director. It can refer to the name of the file by itself (harold), the name plus the file extension (harold.shp), or the whole path of a file up to and including the file name extension (C:\mygisdata\shapefiles\harold.shp)

equator

The parallel of reference that is equidistant from the poles and defines the origin of latitude values.

normalize

The process of dividing one numeric attribute value by another to minimize difference in values based on the size of areas or the number of features in each area. For example, normalizing (dividing) total population by total area yields population per unit area, or density.

classification methods

The process of sorting or arranging entities into groups or categories. Some methods include grouping by the same symbol, usually defined in a legend.

Classification

The process of sorting or arranging entities into groups or categories; on a map, process of representing members of a group by the same symbol, usually defined in a legend.

byte

The smallest addressable unit of data storage within a computer; almost always equivalent to 8 bits and containing one character.

pixel

The smallest unit of information in an image or raster map, usually square or rectangular. Pixel is often used synonymously with cell. The smallest element of a display device, such as a video monitor, that can be independently assigned attributes, such as color and intensity. Pixel is an abbreviation for picture element.

cell*

The smallest unit of information in raster data, usually square in shape. In a map or GIS dataset, each cell represents a portion of the earth, such as a square meter or square mile, and usually has an attribute value associated with it, such as soil type or vegetation class. A pixel A small drawing, usually of a frequently used or complex symbol, notation, or detail. Cells are similar to blocks in AutoCAD drawings.

elevation

The vertical distance of a point or object above or below a reference surface or datum (generally mean sea level). Elevation generally refers to the vertical height of land.

relational join

The way by which two or more table sfrom a RDMS can be joined together based on one or more common items or keys.

features: area, line, point*

There are three different types of feature: area (a 2D polygon with a plane), line (2D line with no width), and point (a 1D point with no area).***

export file

To move data from one computer system to another, and often, in the process, from one file format to another.

desktop mapping

Using ArcGIS for personal use. All the documents can be edited by one person. Compared to ArcGIS enterprise that is usually located on a server. ***

polyline

[ESRI software] In ArcGIS software, a shape defined by one or more paths, in which a path is a series of connected segments. If a polyline has more than one path (a multipart polyline), the paths may either branch or be discontinuous. http://downloads.esri.com/support/gisDictionary/images/polylines.gif

table of contents in "View Documents"

[ESRI software] In ArcGIS, a tabbed list of data frames and layers (or tables) on a map that shows how the data is symbolized, the source of the data, and whether or not each layer is selectable.

view

[ESRI software] In ArcGIS, a way to see the contents of a selected item in the Catalog tree in ArcCatalog. [ESRI software] In ArcView 3, one of the five types of documents that can be contained within a project file. A view is used for displaying, querying, and analyzing geographic themes. A view consists of a table of contents, which lists all the geographic themes contained in the view, and a map area on which geographic themes are displayed.

properties: layout, theme, view

[ESRI software] an attribute of an object defining one of its characteristics or an aspect of its behavior. layout, theme, view...

TCP/IP*

[Internet] Acronym for Transmission Control Protocol/Internet Protocol. - protocol for Internet traffic. - sets of rules that allow computers to send and receive data over networks.

topographic map

[cartography] A map that represents the vertical and horizontal positions of features, showing relief in some measurable form, such as contour lines, hypsometric tints, and relief shading.

text label

[cartography] Text placed next to a feature on a map to describe or identify it.

resolution

[cartography] The detail with which a map depicts the location and shape of geographic features. The larger the map scale, the higher the possible resolution. As scale decreases, resolution diminishes and feature boundaries must be smoothed, simplified, or not shown at all; for example, small areas may have to be represented as points. [graphics (computing)] the dimensions represented by each cell or pixel in a raster.

symbology*

[cartography] The set of conventions, rules, or encoding systems that define how geographic features are represented with symbols on a map. A characteristic of a map feature may influence the size, color, and shape of the symbol used.

State Plane Coordinate System*

[coordinate systems] A group of planar coordinate systems based on the division of the United States into more than 130 zones to minimize distortion caused by map projections. Each zone has its own map projection and parameters and uses either the NAD27 or NAD83 horizontal datum. The Lambert conformal conic projection is used for states that extend mostly east-west, while transverse Mercator is used for those that extend mostly north-south. The oblique Mercator projection is used for the panhandle of Alaska.

vector

[data models] A coordinate-based data model that represents geographic features as points, lines, and polygons. Each point feature is represented as a single coordinate pair, while line and polygon features are represented as ordered lists of vertices. Attributes are associated with each vector feature, as opposed to a raster data model, which associates attributes with grid cells. http://downloads.esri.com/support/gisDictionary/images/vector.gif [graphics (computing)] Any quantity that has both magnitude and direction.

surface

[data models] A geographic phenomenon represented as a set of continuous data (such as elevation, geological boundaries, or air pollution); a spatial distribution which associates a single value with each position in a plane, usually associated with continuous attributes. http://downloads.esri.com/support/gisDictionary/images/surface.gif

shape

[data models] The characteristic appearance or visible form of a geographic object as represented on a map. A GIS uses points, lines, and polygons to represent the shapes of geographic objects.

polygon feature

[data models] a map feature that bounds an area at a given scale, such as a country on a world map or a district on a city map. [ESRI software] In ArcGIS software, a digital map feature that represents a place or thing that has area at a given scale. A polygon feature may have one or more parts. For example, a building footprint is typically a polygon feature with one part. If the building has a detached unit, it might be represented as a multipart feature with discontinuous parts. If the detached unit is in an interior courtyard, the building might be represented as a multipart feature with nested parts. A multipart polygon feature is associated with a single record in an attribute table.

raster

[data models] a spatial data model that defines space as an array of equally sized cells arranged in rows and columns, and composed of single or multiple bands. Each cell contains an attribute value and location coordinates. Unlike a vector structure, which stores coordinates explicitly, raster coordinates are contained in the ordering of the matrix. Groups of cells that share the same value represent the same type of geographic feature. http://downloads.esri.com/support/gisDictionary/images/raster.gif

precision

[data quality] The number of significant digits used to store numbers, particularly coordinate values. Precision is important for accurate feature representation, analysis, and mapping

single precision

[data quality] a level of coordinate exactness based on the number of significant digits that can be stored for each coordinate. Single precision numbers store up to seven significant digits for each coordinate, retaining a precision of plus or minus 5 meters in an extent of 1,000,000 meters. Datasets can be stored in either single or double precision coordinates.

tabular data

[data storage] Descriptive information, usually alphanumeric, that is stored in rows and columns in a database and can be linked to spatial data.

spatial data

[data structures] Information about the locations and hsapes of geographic features and the relationships between them, usually stored as coordinates and topology. [data models] any data that can be mapped.

RDBMS*

[database structures] (Relational Database Management System) A type of database in which data is organized across one or more tables. Tables are associated with each other through common fields called keys. In contrast to other database structures, an RDBMS requires few assumptions about how data is related or how it will be extracted from the database.

row

[database structures] A record in a table [database structures] the horizontal dimension of a table composed of a set of columns containing one data item each.

record

[database structures] A set of related data fields, often a row in a database, containing all the attribute values for a single feature. For example, in an address database, the fields that together provide the address for a specific individual comprise one record. In the SQL query language, a record is anologous to a tuple. http://downloads.esri.com/support/gisDictionary/images/record.gif [database structures] a row in a table.

spatial database

[database structures] A structured collection of spatial data and its related attribute data, organized for efficient storage and retrieval.

relational database

[database structures] a data structure in which collections of tables are logically associated with each other by shared fields.

primary key*

[database structures] an attribute or set of attributes in a database that uniquely identifies each record. A primary key allows no duplicate values and cannot be null.

thematic map

[map design] A map designed to convey information about a single topic or theme, such as population density or geology.

SQL

[programming] (Structured Query Language) A syntax for retrieving and manipulating data from a relational database. SQL has become an industry standard query language in most relational database management systems.

query

[programming] A request to select features or records from a database. A query is often written as a statement or logical expression.

tool

[software] A command that requires interaction with the GUI before an action is performed. For example, a zoom tool requires a user to use the mouse to click on or draw a box over a digital map before the tool will cause the map to be redrawn at a larger scale. [ESRI software] A geoprocessing command in ArcGIS that performs such specific tasks as clip, split, erase, or buffer.

user interface

[software] The aspects of a computer system or program with which a software user can interact, and the commands and mechanisms used to control its operation and input data.

spatial query

[spatial analysis] A statement or logical expression that selects geographic features based on location or spatial relationship. For example, a spatial query might find which points are contained within a polygon or set of polygons, find features within a specified distance of a feature, or find features that are adjacent to each other.

spatial join

[spatial analysis] A type of table join operation in which fields from one layer's attribute table are appended to another layer's attribute table based on the relative locations of the features in the two layers.

symbol

[symbology] A graphic used to represent a geographic feature or class of features. Symbols can look like what they represent (trees, railroads, houses), or they can be abstract shapes (points, lines, polygons) or characters. Symbols are usually explained in a map legend. http://downloads.esri.com/support/gisDictionary/images/symbol.gif

Data Set

a file of related records on a computer-readable medium such as a disk.

map display

a graphic representation of a map on a computer screen.

Boolean operator

a logical operator used in the formulation of a Boolean expression. Common Boolean operators include AND, which specifies a combination of conditions (A and B must be true); OR, which specifies a list of alternative conditions (A or B must be true); NOT, which negates a condition (A but not B must be true); and XOR (exclusive or), which makes conditions mutually exclusive (A or B may be true but not both A and B).

image

a representation or description of a scene, typically produced by an optical or electronic device, such as a camera or a scanning radiometer. Common examples include remotely sensed data (for example, satellite data), scanned data, and photographs. In ArcGIS, a raster dataset.

shape files

a vector data storage format (shapefile) for storing the location, shape, and attributes of geographic features. A shapefile is stored in a set of related files and contains one feature class.

Boolean expression*

an expression, named for the English mathematician George Boole (1815-1864), that results in a true or false (logical) condition. For example, in the Boolean expression "HEIGHT > 70 AND DIAMETER = 100," all locations where the height is greater than 70 and the diameter is equal to 100 would be given a value of 1, or true, and all locations where this criteria is not met would be given a value of 0, or false.

data formats readable by ArcGIS

apr - arcview project file dat - generic data file extension / INFO attribute file dbf - DBASE tabular data file / Shapefile attribute table file e00 - ARC/INFO export file exe - DOS/Windows executable file gif - Image file htm - hypertext markup, 3 html - hypertext markup language, UNIX version jpg - Image file (Joint Photographic Experts Group) mdb - Microsoft Access file met - Metadata text file prj - projections definition file shp - shapefile (stores feature geometry) shx - shapefile (stores file lookup index) sid - MrSID image file stn - Geocoding standardization file tiff - Image file (Tag Image Format file) txt - text file (usually ASCII) xls - microsoft excel file xml - XML file (for metadata)

data types: image, spatial, & tabular **

image: pictures. spatial: data on a map. tabular: data in a table.

ArcGIS documents

it is the map blah blah

linking tables

one to many - only link many to many - link or join one to one - link or join many to one - link or join

map

the document used in ArcMap to display and work with geographic data. In ArcMap, a map contains one or more layers of geographic data, contained in data frames, and various supporting map elements, such as a scale bar.

tool bar & button bar

toolbar: [software] A graphical user interface (GUI) with buttons that allow users to execute software commands. button bar?