Welcome to the Census Academy OpenMapping Series. You have chosen the Geographic Information
Systems Learning Path. In the following three modules you will learn what makes the GIS,
how to download and install your own desktop GIS, and how to design your own maps in QGIS
using data from the US Census Bureau and other sources. This is GIS Module 1, Introduction
to GIS, in this Module you will learn about the uses and components of a geographic information
system or GIS. You'll be shown how to download and install your own free and open-source
desktop GIS called QGIS. The Module will also take you through data and GIS, and introduce
datasets from the US Census Bureau. Links to additional QJ s help and technical support
will also be provided. Part 1, what is a GIS? GIS software enables us to visualize spatial
data, analyze those data, and answer location-based questions. With the GIS application, you can
identify distributions, relationships, and trends within data, combine and overlay data
to solve problems, map and model scenarios, and make predictions based on spatial data
trends. For example, GIS is used to find directions and navigate from your smartphone or even
analyze crop yields for more effective agricultural production. GIS can be applied to nearly every
industry or topic, from disaster risk management to business.
GIS constantly informs everyday life. Organizations use GIS data to learn the what, when, where,
and whys of your purchasing behavior, so they can better target customers and market accordingly.
In urban planning, there are numerous benefits to using GIS. GIS takes into consideration
many different factors in building a city, and multi-layered mapping within a GIS allows
the municipal planning committee to see layers with different types of information, all at
once. For example, if you're looking to build a future residential development, you can
compare that to a location of a floodplain, access to schools, and access to emergency
facilities, such as police, fire, and hospitals. As you can see through all of its applications,
GIS is quite a powerful tool; GIS is not run by the computers but rather by people, it
requires a large amount of analysis modeling and other skills. Using a GIS is not only
important for developing in urban areas. It is almost necessary in today's fast-moving
and highly technological landscape. This series will help you get you on your way to using
this technology. In a GIS, a map is made up of layers. As shown in the image on the slide,
each layer represents a real-world feature. This is, anything you can see in the landscape
or on the ground. In this image, one layer represents land use, another elevation, the
next has information about buildings, and after that, there's a layer with the road
network. If you put all of these layers together, you'll get an overview of the area. These
layers are either going to be in a vector or a raster format. Vector format layers are
composed of paths and mathematically built to show an image. All vector map features
fall into one of three geometric types: points, lines, and polygons. Points, also called nodes,
represent features with an XY coordinate that is a latitude and longitude such as trees,
fence posts, and addresses. Lines also called ways, are made up of linearly connected points,
and represent features such as roads, rivers, and electrical lines. Polygons also called
areas, represent land uses, building footprints, and other enclosed areas, such as lakes and
soccer fields. We will mainly be using vector layers in these modules vector layers are
supported by attribute tables. Think of them like geospatial spreadsheets. The example
in the screen shows a vector layer of the United States. Each state represents a feature
within the vector layer and is represented as a row within the attribute table. Additional
data such as, population can be added for each State in the columns. These attributes
will allow you to create thematic maps. For example, you might design a map showing population
density across the United States. You will learn more about attribute tables in module
2. The second data type is a raster format, which are image files made up of pixels. Think
of them as photographs. Raster layers are often used as base maps such as satellite
images, scan maps, or even land use land cover data. Raster provides the best format to represent
data that changes continuously across the landscape such as, rainfall or elevation.
A GIS relies on data and gives you the ability to query, analyze, and visualize those data
to answer questions and test theories. Spatial data enhance the value of information. Imagine
trying to stack two Excel spreadsheets in order to see a pattern, kind of difficult
right? However, in a GIS this is possible, and as they say, a picture or map is worth
a thousand words. In this series, we will be using Geographic data from the US Census
Bureau. The census has been collecting population data since the 1790s. And these data play
an integral role in the life of an American. At the national level census information is
used to plan the provision of health care, education, employment, transport, and more.
The census is also an important economic tool. This series will introduce you to the tiger
and American Community Survey census data sets. Now it is time to download your own
desktop GIS software. The program we use in this series is called QGIS the free and open
source software and an official project of the open source geospatial foundation. As
a volunteer-driven project, QGIS welcomes contributions in the form of code, bug fixes,
bug reports, documentation, advocacy, and supporting other users on the mailing list
and GIS stack exchange.com. You can find more information and documentation at QGIS.org.
This GIS path will introduce you to the key functions of QGIS and in just a few short
lessons you'll making your own printed Maps. The first step is to open a browser on your
desktop and navigate to QGIS.org. You will be presented with the homepage of the QGIS
project. Scroll down, and click the download now button in the bottom left corner. This
will open the download option in this series we will be using the stable long-term release
version 2.18. You will be prompted to save the file, save the program to your desktop.
While you are awaiting the download, take some time to explore the QGIS website and
learn more about the project. If your computer uses the MAC OS X, scroll down to MAC and
expand the section. This version will require a separate download of dependency frameworks
that will all be found in the same download link. Click the KYNGCHAOS QGIS download page
link. A new window will open, presenting download options. Scroll down to the long-term support
section, and click on the QGIS 2.1 8.15 link to begin the download. You'll be prompted
to save the file, save the file to your desktop. Please note that there will be for additional
installation files that are all necessary to run the program. Go back to QGIS.org during
the download to explore more about the project. Once you have downloaded the file, click the
file to Open and Run the installation. Additional technical support can be found at these links.
Once the installation is complete, congratulations you are ready to move on to GIS MODULE 2 QGIS
Basics.