In GIS Geographic Information Systems the software used to create, store, and manage spatial data Data that deals with location, such as lists of addresses, the footprint of a building, the boundaries of cities and counties, etc. , analyze spatial problems, and display the data in cartographic layouts Geographic Information Sciences , we work with three categories of data - primary, secondary, and derived data New spatial datasets created by processing or analyzing existing primary or secondary data In geospatial science, secondary data refers to spatial information that was originally collected by someone else for a different purpose, which you are now using for your own analysis or research. through geoprocessing operations, spatial analysis, or modeling techniques . These aren't unique to GIS Geographic Information Systems the software used to create, store, and manage spatial data Data that deals with location, such as lists of addresses, the footprint of a building, the boundaries of cities and counties, etc. , analyze spatial problems, and display the data in cartographic layouts Geographic Information Sciences - many sciences use similar classifications - but within our field, they have specific meanings.
Primary data is what you collect yourself, either by digitizing The action of creating vector data in any sort of digital science or art, is simply denoting a type of graphical representation using straight lines to construct the outlines of objects by defining the location of each vertex pl. vertices One of a set of ordered x,y coordinate pairs that defines the shape of a line or polygon feature. utilizing drawing pad and puck (manual or hardcopy digitizing) or a computer with a mouse (heads-up or on-screen digitizing) while, most often, looking at and tracing aerial or satellite imagery. features from aerial and satellite imagery or gathering field measurements with GPS Global Positioning System: A satellite-based navigation system owned and operated by the United States Department of Defense that provides location and time information anywhere on Earth. devices. Both methods involve direct interaction with the landscape in a deliberate, hands-on way.
Secondary data comes from other sources - existing datasets created by someone else that you download or obtain for your own purposes.
Derived data is anything you create by running geoprocessing tools on primary or secondary data In geospatial science, secondary data refers to spatial information that was originally collected by someone else for a different purpose, which you are now using for your own analysis or research. (we'll dig into geoprocessing in Chapter Seven).
Primary data generally carries more weight in analysis because it hasn't passed through processing steps where errors might creep in from improper tool use, misunderstandings about the data, or other mishaps (Chapter Eight covers this in detail).
In this chapter, we'll explore manual and heads-up digitizing The action of creating vector data in any sort of digital science or art, is simply denoting a type of graphical representation using straight lines to construct the outlines of objects by defining the location of each vertex pl. vertices One of a set of ordered x,y coordinate pairs that defines the shape of a line or polygon feature. utilizing drawing pad and puck (manual or hardcopy digitizing) or a computer with a mouse (heads-up or on-screen digitizing) while, most often, looking at and tracing aerial or satellite imagery. , get a basic understanding of remote sensing, learn methods for converting paper maps to digital formats, turn postal addresses into coordinates through geocoding The process of converting text-based location descriptions (typically street addresses) into geographic coordinates ( latitude also known as 'parallels' the east-west portion of a geographic grid measured with angles between 0 and 90° /longitude). , collect data using smartphone GPS Global Positioning System: A satellite-based navigation system owned and operated by the United States Department of Defense that provides location and time information anywhere on Earth. apps and commercial receivers, create data through crowdsourcing Geospatial Science: Refers to the collection, creation, or validation of geographic data by a large group of distributed contributors, typically volunteers, rather than by professional cartographers or official agencies. , and modify existing datasets. Creating and correcting data are the two most common tasks GIS Geographic Information Systems the software used to create, store, and manage spatial data Data that deals with location, such as lists of addresses, the footprint of a building, the boundaries of cities and counties, etc. , analyze spatial problems, and display the data in cartographic layouts Geographic Information Sciences technicians do every day, so having a solid grasp of the what and why behind data creation and editing is essential.