ArcGIS

ArcGIS is a product suite developed by Environmental Systems Research Institute (Esri), that is comprised of several technologies ranging from the desktop and server, to the hand held device or open source client. These technologies integrate together allowing someone using the software to create data, perform advanced geospatial analysis, and publish it out as a service so that it can be consumed in web applications, mobile devices, or other desktop software.

ArcGIS can be considered an integrated collection of GIS software products that provides a standards-based platform for spatial analysis, data management, and mapping. ArcGIS is scalable and can be integrated with other enterprise systems such as work order management, business intelligence, and executive dashboards.

Product history
Prior to the ArcGIS suite, Esri had focused its software development on the command line Arc/INFO Workstation program and several Graphical User Interface-based products such as the ArcView GIS 3.x desktop program. Other Esri products included MapObjects, a programming library for developers, and ArcSDE as a Relational database management system. The various products had branched out into multiple source trees and did not integrate well with one another. In January 1997, Esri decided to revamp its GIS software platform, creating a single integrated software architecture.

ArcGIS 8.x
In late 1999, Esri released ArcGIS 8.0, which ran on the Microsoft Windows operating system. ArcGIS combined the visual user-interface aspect of ArcView GIS 3.x interface with some of the power from the Arc/INFO version 7.2 workstation. This pairing resulted in a new software suite called ArcGIS, which included the command-line ArcInfo workstation (v8.0) and a new graphical user interface application called ArcMap (v8.0) incorporating some of the functionality of ArcInfo with a more intuitive interface, as well as an ArcGIS file management application called ArcCatalog (v8.0). The release of the ArcGIS suite constituted a major change in Esri's software offerings, aligning all their client and server products under one software architecture known as ArcGIS, developed using Microsoft Windows Component Object Model (COM) standards.

One major difference is the programming (scripting) languages available to customize or extend the software to suit particular user needs. In the transition to ArcGIS, Esri dropped support of its application-specific scripting languages, Avenue and the ARC Macro Language (AML), in favour of Visual Basic for Applications scripting and open access to ArcGIS components using the Microsoft COM standards. ArcGIS is designed to store data in a proprietary RDBMS format, known as Geodatabase. ArcGIS 8.x introduced other new features, including on-the-fly Map projections, and annotation in the database.

ArcGIS 9.x
ArcGIS 9.0 was released in May 2004, which included ArcGIS Server and ArcGIS Engine for developers. The current version of the ArcGIS software is 9.3.1. The ArcGIS 9 release includes a geoprocessing environment that allows execution of traditional GIS processing tools (such as clipping, overlay, and spatial analysis) interactively or from any scripting language that supports COM standards. Although the most popular of these is Python, others have been used, especially Perl and VBScript. ArcGIS 9 includes a visual programming environment, similar to ERDAS IMAGINE's Model Maker (released in 1994, v8.0.2). The Esri version is called ModelBuilder and as does the ERDAS IMAGINE version allows users to graphically link geoprocessing tools into new tools called models. These models can be executed directly or exported to scripting languages which can then execute in batch mode (launched from a command line), or they can undergo further editing to add branching or looping.

ArcGIS 10.x
ArcGIS 10.0 was announced on January 11, 2010, and was released on June 29, 2010. This release was formerly referred to as ArcGIS 9.4, but due to feedback from the user community and major improvements to the the functionality and a new UI for ArcGIS Desktop it was renamed to ArcGIS 10. Listen to a podcast by Jack Dangermond explaining the reasons for this change.

Name Changes in 10.1
Introduced with release 10.1 are a series of name changes to the ArcGIS product line. The reason for these modifications is to reinforce the fact that, regardless of where and how ArcGIS is used, it is the same system.

Geodatabase
Older Esri products, including ArcView 3.x, worked with data in the Shapefile format. ArcInfo Workstation handled coverages, which stored Topology information about the spatial data. Coverages, which were introduced in 1981 when ArcInfo was first released, has limitations in how it handles types of features. Some features, such as roads with street intersections or overpasses and underpasses, should be handled differently than other types of features.

ArcGIS is built around the Geodatabase, which uses an object-relational database approach for storing spatial data. A geodatabase is a "container" for holding datasets, tying together the spatial features with attributes. The geodatabase can also contain Topology information, and can model behavior of features, such as road intersections, with rules on how features relate to one another. When working with geodatabases, it is important to understand about feature classes which are a set of features, represented with points, lines, or polygons. With shapefiles, each file can only handle one type of feature. A geodatabase can store multiple feature classes or type of features within one file.

Geodatabases in ArcGIS can be stored in three different ways including as a "file geodatabase", "personal geodatabase", and "ArcSDE geodatabase". Personal geodatabases store data in Microsoft Access files, using a BLOB field to store the Geometry data. The OGR library is able to handle this file type, to convert it to other file formats. Database administration tasks for personal geodatabases, such as managing users and creating backups, can be done through ArcCatalog. Personal geodatabases, which are based on Microsoft Access, run only on Microsoft Windows and have a 2 gigabyte size limit. Enterprise (multi-user) level geodatabases are handled using ArcSDE, which interfaces with high-end DBMS such as Oracle, Microsoft SQL Server, DB2 and Informix to handle database management aspects, while ArcGIS deals with spatial data management. Enterprise level geodatabases support database replication, versioning and Transaction management, and is cross-platform compatible, able to run on Linux, Windows, and Solaris.

Components and product levels
ArcGIS consists of Desktop GIS products, as well as GIS products that run on a server, or on a mobile device. There is also an Online GIS component.

License levels
ArcGIS Desktop is available at different license levels, with increasing functionality.


 * ArcReader (freeware, viewer) is a basic data viewer for Maps and GIS data published in the proprietary Esri format using ArcGIS Publisher. The software also provides some basic tools for map viewing, printing and querying of spatial data. ArcReader is included with any of the ArcGIS suite of products, and is also available for free to download. ArcReader only works with pre-authored published map files, created with ArcGIS Publisher.


 * ArcGIS for Desktop Basic (formerly ArcView) is the entry level of ArcGIS licensing offered. With ArcGIS for Desktop Basic, one is able to view and edit GIS data held in flat files, or view data stored in a Relational database management system by accessing it through ArcSDE.


 * ArcGIS for Desktop Standard (formerly ArcEditor) is the midlevel software suite designed for advanced editing of spatial data published in the proprietary Esri format. It provides tools for the creation of map and spatial data used in GIS, including the ability of editing geodatabase files and data, multiuser geodatabase editing, versioning, raster data editing and vectorization, advanced vector data editing, managing coverages, coordinated geometry (COGO), and editing geometric networks. ArcGIS for Desktop Standard is not intended for advanced spatial analysis.


 * ArcGIS for Desktop Advanced (formerly ArcInfo) allows users the most flexibility and control in "all aspects of data building, modeling, analysis, and map display." ArcGIS for Desktop Advanced includes increased capability in the areas of spatial analysis, geoprocessing, data management, and others.

Other desktop GIS software include ArcGIS Explorer and ArcGIS Engine. ArcGIS Explorer is a GIS viewer which can work as a client for ArcGIS Server, ArcIMS, ArcGIS Online, ArcWeb Services and Web Map Service (WMS).

Components
ArcGIS Desktop consists of several integrated applications, including ArcMap, ArcCatalog, ArcToolbox, and ArcGlobe. ArcCatalog is the data management application, used to browse datasets and files on one's computer, database, or other sources. In addition to showing what data is available, ArcCatalog also allows users to preview the data on a map. ArcCatalog also provides the ability to view and manage Metadata for spatial datasets. ArcMap is the application used to view, edit and query geospatial data, and create Maps. The ArcMap inferface has two main sections, including a Table of Contents on the left and the data frame(s) which display the map. Items in the table of contents correspond with layers on the map. ArcToolbox contains geoprocessing, data conversion, and analysis tools, along with much of the functionality in ArcInfo. It is also possible to use Batch processing with ArcToolbox, for frequently repeated tasks.

Extensions
There are a number of software extensions for ArcGIS Desktop to provided added functionality, including 3D Analyst, Spatial Analyst, Network Analyst, Survey Analyst, Tracking Analyst and Geostatistical Analyst. Advanced map labeling is available with the Maplex for ArcGIS extension, as an add-on to ArcView and ArcEditor and is bundled with ArcInfo. Numerous extensions have also been developed by third-parties, such as XTools Pro and MAP2PDF for creating Georeferenced pdfs (GeoPDF), ERDAS' Image Analysis and Stereo Analyst for ArcGIS, and ISM's PurVIEW, which converts Arc- desktops into precise stereo-viewing windows to work with geo-referenced stereoscopic image models for accurate geodatabase-direct editing or feature digitizing.

Server GIS
Server GIS products include ArcIMS, ArcGIS Server (which includes ArcSDE), and ArcGIS Image Server.

Product levels
ArcGIS Server is available at three different product levels with increasing levels of functionality: Basic, Standard, and Advanced Editions. It is also available at two different "capacity" levels: Workgroup (single machine) and Enterprise (multi-user database).

Components
ArcGIS Server comes with SQL Server Express DBMS embedded, and can work with enterprise DBMS such as SQL Server Enterprise and Oracle. The Esri Developer Network (EDN) includes ArcObjects and other tools for building custom software applications, and ArcGIS Engine provides a programming interface for developers.

Extensions

 * 3D Extension
 * Geostatistical Extension
 * Network Extension
 * Spatial Extension
 * Data Interoperability Extension
 * Image Extension
 * Job Tracking Extension
 * Geoportal Extension
 * Schematics Extension

Mobile GIS
ArcGIS Mobile and ArcPad are products designed for mobile devices. ArcGIS Mobile is a Software development kit for developers to use to create applications for mobile devices, such as smartphones or tablet PCs. If connected to the Internet, mobile applications can connect to ArcGIS Server to access or update data.

Online GIS
Online GIS products include ArcGIS Online and ArcWeb Services

Sales
ArcGIS Desktop products and ArcPad are available with a single-use license. Most products are also available with concurrent-use license, while development server licenses and other types of software licenses are available for other products. Single-use products can be purchased online from the Esri Store, while all ArcGIS products are available through a sales representative or reseller. Annual software maintenance and support is also available for ArcGIS. While there are alternative products available from other traditional vendors such as MapInfo and Intergraph, Esri has a dominant share of the GIS software market with its software used by 78% of GIS professionals.

Criticisms
Esri's change to the ArcGIS platform rendered incompatible an extensive range of user-developed and third-party add-on software and scripts. A substantial user base resists migrating to ArcGIS because of changes in scripting capability, functionality, operating system (ArcGIS Desktop software was developed exclusively for the Microsoft Windows operating system), as well as the significantly larger system resources required by the ArcGIS system. Esri has continued support for these users. ArcView 3.x is still available for purchase, and ArcInfo Workstation is still included in a full ArcGIS ArcInfo licence to provide some editing and file conversion functionality that has not been included to date in ArcGIS.

ArcMap and other ArcGIS applications have a tendency to crash from time to time. ArcGIS Desktop 9.1 had bugs when exporting maps as PDF files. Esri has issued a number of service packs for ArcGIS Desktop and other products, which include numerous bug fixes, along with feature enhancements. Other issues with ArcGIS include high prices for the products, proprietary formats, and difficulties of porting data between Esri and other GIS software.