Indicates questions asking about the use and meaning of specific technical words in GIS.

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60
votes
7answers
85k views

What is the difference between DEM, DSM and DTM?

I am listing some of the acronyms used in our work and had to stop to think about whether to list these together or separately: DEM: Digital Elevation Model DSM: Digital Surface Model DTM: Digital ...
25
votes
2answers
2k views

Why do we use the terms “longitude” and “latitude” for a spherical body?

To specify a geographic coordinate we use the terms “longitude” and “latitude”. Far as I know, these terms derive from the Latin latitudo (= breadth) and longitudo (= length). In German we use the ...
8
votes
2answers
3k views

What are LiDAR returns?

Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system.
6
votes
3answers
7k views

Spatial data? Geodata? Geographic Data? Geospatial data?

Language changes all the time and I see various uses of the words defining the data we use in GIS in our day-to-day lives. But what's right? Is there a right answer out there that we would all agree ...
4
votes
3answers
1k views

Difference between lon and lng [closed]

When browsing the web and documentation I see the abbreviation lon and lng used for the longitude part of geometry. I was wondering if there is any difference between lng and lon.
2
votes
2answers
193 views

Terminology for distinguishing ArcPy installed with ArcGIS 10.x for Desktop from that which comes with ArcGIS Pro?

ArcGIS Pro uses Python 3 whereas the other ArcGIS for Desktop applications (ArcMap, ArcCatalog, ArcScene and ArcGlobe) use Python 2 and the changes introduced with ArcGIS Pro were significant ...
9
votes
1answer
114k views

What is the difference between Vector and Raster data models? [duplicate]

From: http://support.esri.com/en/knowledgebase/GISDictionary/term/vector%20data%20model vector data model: [data models] A representation of the world using points, lines, and polygons. Vector ...
7
votes
3answers
239 views

What's a term for Sea Level Distance which is usable by novice users?

I've been using the term Sea Level Distance to describe the total length of a line string where I ignore the elevation and just calculate the distance from point to point along the ellipsoid and sum ...
4
votes
1answer
759 views

Correct use of the terms geographic, path, and Euclidean distance

I often use the terms geographic and Euclidean distance interchangeably when referring to the length of the shortest straight-line distance between two points on a map. Is this correct? I use the ...
0
votes
2answers
25 views

Describing geographic characteristics by lat/long?

I'm not sure of the right terminology to use to google for a database of information. The data in the database should list geographic characteristics of an arbitrary lat/long. Stuff like height ...