Glossary             [A-D] - [E-J] - [K-P] - [Q-S] - [T-Z]

Earnings
Earnings is defined as the algebraic sum of wage or salary income and net income from self-employment. Earnings represent the amount of income received regularly before deductions for personal income taxes, Social Security, bond purchases, union dues, Medicare deductions, etc.
Related term: Income

Economic census
Collective name for the censuses of construction, manufactures, minerals, minority- and women-owned businesses, retail trade, service industries, transportation, and wholesale trade, conducted by the Census Bureau every five years, in years ending in 2 and 7.

Ecoregions 3
A large region, usually spanning several million hectares, characterized by having similar biota, climate, and physiography (topography, hydrology, etc).

Educational attainment
Refers to the highest level of education completed in terms of the highest degree or the highest level of schooling completed.

Elementary school
A school inclusive of kindergarten through either the eighth or ninth grade, or the first through either the eighth or ninth grade. It can include both elementary and intermediate or middle schools.
Related terms: High school

Elevation*
The vertical height above a datum, in units such as meters or feet.

Employed
Employed includes all civilians 16 years old and over who were either (1) "at work" -- those who did any work at all during the reference week as paid employees, worked in their own business or profession, worked on their own farm, or worked 15 hours or more as unpaid workers on a family farm or in a family business; or (2) were "with a job but not at work" -- those who did not work during the reference week but had jobs or businesses from which they were temporarily absent due to illness, bad weather, industrial dispute, vacation, or other personal reasons. Excluded from the employed are people whose only activity consisted of work around the house or unpaid volunteer work for religious, charitable, and similar organizations; also excluded are people on active duty in the United States Armed Forces. The reference week is the calendar week preceding the date on which the respondents completed their questionnaires or were interviewed. This week may not be the same for all respondents.
Related terms: Labor force, Unemployed, Worker

EPA Regions 2
There are 10 EPA Regional Offices covering the United States. Each EPA Regional Office is responsible within its states for the execution of the Agency's programs.

Enumeration map*
Map designed to show one census enumerator the geographic extent and address ranges within their district.

Environment and Population (Map theme)
This map theme provides a variety of data layers on environmental features and population characteristics. You can create maps that allow you to examine the relationships between people and the environment. It focuses on communities such as counties, census tracts, and congressional districts. The information comes primarily from federal and state sources such as the U.S. Bureau of the Census, the U.S. Environmental Protection Agency, Arizona Dept. of Water Resources, and the Arizona Dept. of Health Services. You can combine together the percent minorities, location of Superfund sites, and the percent of deaths for selected causes.

Establishment
A business or industrial unit at a single location that distributes goods or performs services.

Export*
The capability of a GIS to write data out into an external file and into a non-native format for use outside the GIS, or in another GIS.

Extent
The coordinates defining the minimum bounding rectangle (that is, xmin, ymin and xmax, ymax) of a data source. All coordinates for the data source fall within this boundary. For example, to view a map at "full extent" means that you will see the entire map zoomed out as far as it can go.

Family
A group of two or more people who reside together and who are related by birth, marriage, or adoption.

Family household (Family)
A family includes a householder and one or more people living in the same household who are related to the householder by birth, marriage, or adoption. All people in a household who are related to the householder are regarded as members of his or her family. A family household may contain people not related to the householder, but those people are not included as part of the householder's family in census tabulations. Thus, the number of family households is equal to the number of families, but family households may include more members than do families. A household can contain only one family for purposes of census tabulations. Not all households contain families since a household may comprise a group of unrelated people or one person living alone.
Related terms: Household, Householder

Family size
Refers to the number of people in a family.

Family type
Refers to how the members of a family are related to one another and the householder. Families may be a "Married Couple Family," "Single Parent Family," "Stepfamily," or "Subfamily."

FAQ*
A list of frequently asked questions, usually posted on a network newsgroup or conference group to save new users the trouble of asking old questions over again.

Fault 3
A fracture or break in the Earth's crust along which one side of the break is pushed up, down, or sideways.

Feature
A representation of a real-world object in a layer on a map.

Federal Information Processing Standards (FIPS)
Standardized system of numeric and/or alphabetic coding issued by the National Institute of Standards and Technology (NIST), an agency of the US Department of Commerce. FIPS codes are assigned for a variety of geographic entities including American Indian Areas, congressional districts, counties, county subdivisions, metropolitan areas, places and states. The purpose in using FIPS codes is to improve the use of data and avoid unnecessary duplication and incompatibility in the collection, processing and dissemination of data.

Female householder, no husband present
A female maintaining a household with no husband of the householder present.

Field*
The contents of one attribute for one record, as written in a file.

File*
Data logically stored together at one location on the storage mechanism of a computer.

Flood 4
An overflow of water onto lands that are used or usable by man and not normally covered by water. Floods have two essential characteristics: The inundation of land is temporary; and the land is adjacent to and inundated by overflow from a river, stream, lake, or ocean.

Flood, 100-year 4
A 100-year flood does not refer to a flood that occurs once every 100 years, but to a flood level with a 1 percent chance of being equaled or exceeded in any given year

Format*
The specific organization of a digital record.

Foster children
Children receiving parental care and guidance although not related through blood or legal ties; placed in care by a government agency.
When a foster child is also a relative, such as a nephew or niece, the child is counted as a related individual rather than a foster child.
Related term: Nonrelatives

FTP (File Transfer Protocol)*
A standardized way to move files between computers. It is a packet switching technique, so that errors in transmission are detected and corrected. FTP allows files, even large ones, to be moved between computers on the Internet or another compatible network.

Full Map
Displays the full extent of the map.

General-purpose map*
A map designed primarily for reference and navigation use.

Geographic coordinates*
The latitude and longitude coordinate system.

Geographic entity
A geographic unit of any type, legal or statistical, such as a state, county, place, county subdivision, census tract, or census block.

Geographic information science*
Research on the generic issues that surround the use of GIS technology, impede its implementation, or emerge from an understanding of its capabilities.

Geographic Information Systems Information 1
Computer hardware and software for storing, retrieving, manipulating, and analyzing spatial data

Geographic pattern*
A spatial distribution explainable as a repetitive distribution.

Geographic search*
A find operation in a GIS that uses spatial properties as its basis.

Geographic(al) information system*
(1) A set of computer tools for analyzing spatial data;
(2) A special case of an information system designed for spatial data;
(3) An approach to the scientific analysis and use of spatial data;
(4) A multibillion- dollar industry and business.

Geography (census)
A collective term referring to the types of geographic areas used by the Census Bureau in its data collection and tabulation operations, including their structure, designations, and relationships to one another.

Geography*
The science concerned with all aspects of the earth's surface, including natural and human divisions, the distribution and differentiation of regions, and the role of humankind in changing the face of the earth.

GIF*
An industry standard raster graphic or image format.

Globe*
A three-dimensional model of the earth made by reducing the representative fraction to less than 1:1.

Grade in which enrolled
The level of enrollment in school, nursery school through college and graduate or professional school.
Related term: Educational attainment

Gradient*
The constant of multiplication in a linear relationship; that is, the rate of increase of a straight line up or down. See also slope.

Gross rent
The amount of the contract rent plus the estimated average monthly cost of utilities (electricity, gas, and water and sewer) and fuels (oil, coal, kerosene, wood, etc.) if these are paid for by the renter (or paid for the renter by someone else). Gross rent is intended to eliminate differentials which result from varying practices with respect to the inclusion of utilities and fuels as part of the rental payment.

Ground Water 5
The supply of fresh water found beneath the Earth's surface, usually in aquifers, which supply wells and springs. Because ground water is a major source of drinking water, there is growing concern over contamination from leaching agricultural or industrial pollutants or leaking underground storage tanks.

Groundwater Basins

Group quarters (GQ)
The Census Bureau classifies all people not living in households as living in group quarters. There are two types of group quarters: institutional (for example, correctional facilities, nursing homes, and mental hospitals) and non-institutional (for example, college dormitories, military barracks, group homes, missions, and shelters).
Related term: Household

Group quarters population
Includes all people not living in households. This term includes those people residing in group quarters as of the date on which a particular survey was conducted. Two general categories of people in group quarters are recognized: 1) the institutionalized population which includes people under formally authorized supervised care or custody in institutions at the time of enumeration (such as correctional institutions, nursing homes, and juvenile institutions) and 2) the noninstitutionalized population which includes all people who live in group quarters other than institutions (such as college dormitories, military quarters, and group homes). The noninstitutionalized population includes all people who live in group quarters other than institutions.
Related terms: Institutionalized population, Noninstitutionalized population
Related terms: 100-Percent data
Related terms: Census (decennial), Long form
Related terms: Reference map, Thematic map

GUI (graphical user interface)*
The set of visual and mechanical tools (such as window, icons, menus, and toolbars, plus a pointing device such as a mouse) through which a user interacts with a computer.

Habitat 5
The place where a population (e.g. human, animal, plant, microorganism) lives and its surroundings, both living and non-living.

High school
Includes schools with either the ninth through the twelfth grade or the tenth through the twelfth grades.
Related terms: Elementary school

Hispanic or Latino origin
For Census 2000, American Community Survey: People who identify with the terms "Hispanic" or "Latino" are those who classify themselves in one of the specific Hispanic or Latino categories listed on the Census 2000 or ACS questionnaire-"Mexican," "Puerto Rican," or "Cuban"-as well as those who indicate that they are "other Spanish, Hispanic, or Latino." Origin can be viewed as the heritage, nationality group, lineage, or country of birth of the person or the person's parents or ancestors before their arrival in the United States. People who identify their origin as Spanish, Hispanic, or Latino may be of any race.

1990 Census of Population and Housing: A self-designated classification for people whose origins are from Spain, the Spanish-speaking countries of Central or South America, the Caribbean, or those identifying themselves generally as Spanish, Spanish-American, etc. Origin can be viewed as ancestry, nationality, or country of birth of the person or person's parents or ancestors prior to their arrival in the United States.
Related terms: Ancestry, Spanish/Hispanic/Latino

Homeowner vacancy rate
The homeowner vacancy rate is the proportion of the homeowner housing inventory which is vacant for sale. It is computed by dividing the number of vacant units for sale only by the sum of owner-occupied units and vacant units that are for sale only, and then multiplying by 100.
Related terms: Owner-occupied housing unit, Rental vacancy rate

Household
A household includes all the people who occupy a housing unit as their usual place of residence.

Household size
The total number of people living in a housing unit.

Household type and relationship
Households are classified by type according to the sex of the householder and the presence of relatives. Examples include: married-couple family; male householder, no wife present; female householder, no husband present; spouse (husband/wife); child; and other relatives.

Householder
The person, or one of the people, in whose name the home is owned, being bought, or rented.
If there is no such person present, any household member 15 years old and over can serve as the householder for the purposes of the census. Two types of householders are distinguished: a family householder and a nonfamily householder. A family householder is a householder living with one or more people related to him or her by birth, marriage, or adoption. The householder and all people in the household related to him are family members. A nonfamily householder is a householder living alone or with nonrelatives only.

Housing unit
A house, an apartment, a mobile home or trailer, a group of rooms, or a single room occupied as separate living quarters, or if vacant, intended for occupancy as separate living quarters. Separate living quarters are those in which the occupants live separately from any other individuals in the building and which have direct access from outside the building or through a common hall. For vacant units, the criteria of separateness and direct access are applied to the intended occupants whenever possible.

Hypertext*
Textual information in which direct links can be made between related text through "hot links," where pointing to a highlighted term moves the user to the text context for that term in the same or a different document.

Identify*
To find a spatial feature by pointing to it interactively on the map with a pointing device such as a mouse.

Image map*
A map that in two dimensions shares many of the characteristics of a map, that is, cartographic geometry, some symbols, a scale and projection, and so on, but is a continuous image taken from an air photo, a satellite image, or a scanner. A scanned paper map used as a backdrop in a GIS becomes an image map.

Import*
The capability of a GIS to bring data in an external file and in a non-native format for use within the GIS.

Income
"Total income" is the sum of the amounts reported separately for wages, salary, commissions, bonuses, or tips; self-employment income from own nonfarm or farm businesses, including proprietorships and partnerships; interest, dividends, net rental income, royalty income, or income from estates and trusts; Social Security or Railroad Retirement income; Supplemental Security Income (SSI); any public assistance or welfare payments from the state or local welfare office; retirement, survivor, or disability pensions; and any other sources of income received regularly such as Veterans' (VA) payments, unemployment compensation, child support, or alimony.
Related term: Earnings

Incorporated place
A type of governmental unit incorporated under state law as a city, town (except the New England states, New York, and Wisconsin), borough (except in Alaska and New York), or village and having legally prescribed limits, powers, and functions.
Related terms: Census designated place (CDP), Place

Industrial Classification
The Economic Census classifies establishments according to the new North American Industry Classification System (NAICS). NAICS codes replace the Standard Industrial Classification (SIC) codes used in previous censuses. NAICS classifies industries using 2-, 3-, 4-, 5-, and 6- digit levels of detail. 2-digit codes represent sectors, the broadest classifications. 6-digit codes represent individual industries in the U.S.
Related terms: Economic census, North American Industry Classification System (NAICS)

Industry (economic)
In the 1997 economic census data, U.S. industries are classified using a 5- or 6- digit NAICS code. Industry groups are represented by classification using a 4 digit NAICS code.
Related term: North American Industry Classification System (NAICS)

Inset*
A map within a map, either at a smaller scale to show relative location, or a larger scale to show detail. An inset may have its own set of cartographic elements, such as a scale and graticule.

Institutionalized population
People under formally authorized, supervised care or custody in institutions at the time of enumeration. Generally, restricted to the institution, under the care or supervision of trained staff, and classified as "patients" or "inmates."
Related terms: Group quarters (GQ), Group quarters population, Noninstitutionalized population

Intensity*
The amount of light emitted or reflected per unit area. A map that has high intensity appears bright.

Internet*
A network of many computer networks. Any computer connected to the Internet can access any of the computers accessible through the network.

* Clarke, Keith C. Getting Started with Geographic Information Systems. 4th edition. Upper Saddle River, N.J., 2003.
1 USGS Gap Analysis Program Handbook
2 EPA Regional Offices - http://www.epa.gov/epahome/aboutepa.htm#regiontext
3 USGS Glossary - http://interactive2.usgs.gov/glossary -Page no longer available.
4 USGS Water Science Glossary of Terms - http://ga.water.usgs.gov/edu/dictionary.html
5 EPA Terms of Environment http://www.epa.gov/OCEPAterms/wterms.html
All other definitions from American Factfinder - http://factfinder.census.gov/servlet/BasicFactsServlet - click on Glossary

For other Glossaries, see http://www.gis.com/whatisgis/glossaries.html