A Gentle Intro To ArcGIS Desktop

The ArcGIS is a tool that provides functionalities to capture, store, query, analyze, visualize and produce different format of output of geographical information. 

ArcGIS is a geographic information system (GIS) for working with maps and geographic information. It is used for creating and using maps, compiling geographic data, analyzing mapped information, sharing and discovering geographic information, using maps and geographic information in a range of applications, and managing geographic information in a database. - Wikipedia

Components of ArcGIS Desktop

·        ArcMap

·        ArcCatalog

·        ArcToolbox

ArcGIS Desktop is comprised of a set of integrated applications, which can be accessible from the start menu of your pc.

ArcMap is the main mapping application which allows you to create maps, perform query, analyze spatial data and finally compose your maps (Map visualization).

The ArcCatalog on the other hand, helps to organize spatial data contained on your pc or other storage locations. It also allows you to search, preview and add data to ArcMap as well as manage metadata.

ArcToolbox can only be accessed within the ArcMap and ArcCatalog window. Unlike ArcMap & ArcCatalog which could be accessed from the start menu of your pc. ArcToolbox contains tools for geoprocessing, data conversion (Such as raster to polygon), projection and a whole lot more.

Software Products – Licensing Level

As with many other application software out there, ArcGIS is made up of more than one software product level. To be more specific, it is made up of three software product levels namely; Basic, Standard & Advanced level. One you should know is that, these products share a common architecture but provides varied levels of functionality.

• ·        Basic Level provides the base mapping and analysis tools.
•      Standard Level provides all basic level capabilities and includes additional processing and advanced processing editing tools.
•     Advanced Level provides both the basic and standard level capabilities plus advanced analysis and processing.

DATA MANAGEMENT (ArcCatalog)

In this session we will be faced with more of practical than just words or text. Visualizing in this session would be better understood.

So we begin by clicking on the Windows start Menu of our pc. Click on all programs and navigate to ArcCatalog or simply use the search bar to bring it out. Click it open, the moment you find it.

You should have a window that looks like the one below once it is opened.

ArcCatalog provides an integrated and unified view of all the data files, databases, and ArcGIS documents available to you. ArcCatalog is also used to document and manage metadata and to define the schemas of geodatabases.

The ArcCatalog interface has two key panels:

• The Catalog Tree panel on the left side shows you a tree view of your GIS contents.
• The contents preview panel on the right shows you information and details about selected items in the tree view.

You can organize your contents in the Catalog tree, make new connections, add new elements (such as datasets), remove elements, rename them, and so on.

ArcCatalog helps you manage all your geographic information items using the Catalog Tree panel to view your files on disk and database connections. By selecting an element in the Catalog tree, you can view its properties, geography, and attributes in the right-hand contents preview panel.

GIS FILE TYPES

Below is a list of some and not all GIS file types. You should also know that these are also common file types one can easily come across while working with a GIS software. In the course of this, these file types will be categorized. So just take note.

Vector GIS File Types: Vector data, unlike raster data is not made up of a grid of pixels. Instead, vector graphics are comprised of vertices and paths which are made up of the three basic symbol types; lines, points and polygons (areas).

So these are the vector GIS file formats that house geospatial data.

·        SHP (Shapefile)

The most common geospatial file type you’ll encounter. Almost all commercial and open source accept shapefile as GIS formats.

You should note that a set of three files that are mandatory makes up a shapefile. These three files are – SHP is the feature geometry, SHX is the shape index position and DBF is the attribute data.

SHP file structure

·        KML/KMZ (Keyhole Markup Language)

This GIS format is XML-based and is primarily used for Google Earth. KML was developed by Keyhole Inc which was later acquired by Google. KMZ (KML-Zipped) replaced KML as being the default Google Earth geospatial format because it is a compressed version of the file. KML/KMZ became an international standard of the Open Geospatial Consortium in 2008.         

·        GDB (File Geodatabase)

The file geodatabase was created by Esri to be a container for storing multiple attribute tables, vector and raster data sets. You should know that, the file geodatabase is the successor of the personal geodatabase – and Esri recommend file geodatabases over personal geodatabases, reason being that - File geodatabases offer structural and performance advantages with fast performance, versatile relationships, compatible storage for rasters, improved spatial indexes, data compression, customizable configuration and about 1 terabyte file size restrictions. Within a geodatabase, shapefiles are referred to as feature classes.

Geodatabase structure

These and more, are common vector GIS file types. You can go check other online sources to get more on vector format.

Raster GIS File types

Raster data is made up of pixels with values (also referred to as grid cells). They are usually regularly-spaced and square but they don’t have to be. Rasters often look pixelated because each pixel is associated with a value or class. Examples are below.

·        GeoTIFF

This is an acronym for Geographic Tagged Image File Format. The GeoTIFF is a raster file type that has become an industry image standard file for GIS and satellite remote sensing applications.

Almost all GIS and image processing software packages come with the TIFF format. GeoTIFFs may be accompanied by other files just as you have in the shapefiles. TFW is the world file that is required to give your raster geolocation. XML optionally accompany GeoTIFFs and are your metadata. AUX out auxiliary files store projections and other information.

·        ESRI Grid

The ESRI Grid allows you to add attribute data to a raster file. You should note that you can only add attributes to integer grids. The attributes are stored in a value attribute tables (VAT) – one record for each unique value in the grid, and the count representing the number of cells. The two types of Esri Grid files are integer and floating point grids. Land cover would be an example of a discrete grid. Each class has a unique integer cell value. Elevation data is an example of a floating point grid. Each cell represents an elevation floating value. Grids usually have no extension.

Still there are more on raster file formats out there, but these are just some of it.

BEGINNING WITH A BLANK DOCUMENT

There are a number of ways to open the ArcMap. You can:

1. · Double (Left) click on the ArcMap shortcut if you already have it on your desktop.
2.   Use the search bar next to the windows start button, type “ArcMap” and click on it once to        load the   ArcMap window.
3.  Click on the windows start menu icon  on the left hand side of your screen, click on all       programs. Look for the ArcGIS folder and navigate to ArcMap.

ArcGIS Blank page

Once you’re able to load the ArcMap, you are greeted with this window above.

Click on the Cancel button to close the dialog box. And then you will have something like the image below

It is that easy. From thence you can connect to folder and add your map data.